ALH Injection Pump / Fuel Solenoid Power

DudaEnergy

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May 4, 2015
Location
Madison, AL
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2003 VW 1.9L
My fuel solenoid isn't getting power. When wired, I see 0v. When the wire isn't connected, it reads 5v. It usually starts (rough) with this condition but I've been dead on the road at random times and could not get power at high speeds. Seems like the valve was partially opening? I discovered the issue when installing a lift pump. So I made a direct connection from the battery to the solenoid and all issues are gone. Now i need to find out where this voltage loss is coming from so I don't have to pop the hood for every trip.

Does anyone have wiring diagrams for this? My first check will be on the plug the power source comes from. I don't know which pins to check which are specific to the fuel solenoid. And if no power there, where will I be checking from there? Are there any relays or other connection points to check? Am I looking at straight wire from relay 109 to this solenoid?

I also have a mysterious power consumption of about 0.5amps when the vehicle is off. It's killed one battery and now the new one has become noticeable. I've checked fuses and found only 0.1mv drop across the 25A fuse for the engine components. All others have 0mv reading. it's also difficult to check these things because the door needs to be open the access the fuse box but you're supposed to leave the car alone for 2 hours so it will enter sleep mode? Is the door light not part of this letting it fall asleep part? I did have car audio equipment installed summer of last year. So I'm thinking of taking it to them since I can't recall power loss issues prior to then. And not sure if there's anything they could have done which would be related to my fuel solenoid not getting proper power?
 

Sprocket

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Have you tried replacing your 109 relay?
 

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Connect a multi-meter to the top of the Solenoid and ground. Have a friend turn on the Ignition. You will see the voltage something above 12 volts and quickly drop off to almost zero!

As far as I can tell, that is normal. I've confirmed this on my 2000 Jetta ALH and the 2002 ALH engine in my 84 Vanagon.

One thing I've not done is see what the volts are while cranking the engine!

The Fuel Cut-off Valve (N109) gets it's power directly from the ECU at T121/120. Leaving the ECU the circuit goes through the Black Connector at 10f/8 and on to the Cut-off Valve. I seriously doubt there is a bad connection in the connector.

Hope this helps!
 

DudaEnergy

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Madison, AL
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2003 VW 1.9L
I did replace relay 109 as the first guess. But considering that relay powers many other things, it's obvious that couldn't have been the issue.

The lack of fuel supply at high speeds could have been a faulty sending unit. It was sluggish when I used an external pump to draw fuel from the tank. So now that there is a lift pump installed, it's difficult to know if that's the issue or not and I can't run the car now without running the lift pump.

The idparts instructions said to tap the power to the relay from the injection pump solenoid. The relay wouldn't turn on with the power from the ignition. It needs a solid 12v. Why would their published instructions say to do this if it won't work? When I called them to ask what was going on they said the pump fuel shut off valve needs a consistent 12v of power to stay open.

Since it gets power directly from the ECU this would mean it does not have any relevance to relay109? I've read on the forums that relay109 is what gives the power to the fuel shutoff valve. Does anyone have a wiring diagram to show which is the case?
 
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KLXD

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If I were running an electric pump I'd use a relay with the cutoff solenoid as the signal. I wouldn't run a pump off it directly.
 

DudaEnergy

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2003 VW 1.9L
If I were running an electric pump I'd use a relay with the cutoff solenoid as the signal. I wouldn't run a pump off it directly.
That's exactly how it's set-up. The 12v relay isn't getting 12v from the fuel shutoff so it can't energize to provide power to the pump.

I did just test my wife's car. Initially 60v shows when the key is turned then it sporadically drops to next to 0 then 0.

I'm throwing the question towards idparts in regards to powering that relay.
 

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
To reiterate my point about the voltage at the solenoid, here is a series of pics taken only seconds apart. This volt gauge is connected to the Solenoid on the IP on the ALH engine in my Vanagon (same test on my 2000 Jetta TDI yielded the same results). This was back in October of 2012, both engines start and run just fine!

Below, when ignition was first turned ON.




Below, a few more seconds later...



Below, a few more seconds later...



And, below, a few more seconds later...




I think you need to find another source of "switched current" for your relay. And, I'd never connect anything, even a relay, to a circuit coming off the ECU. Seems Pins 1 and 2 (large gauge wire) provide power to the ECU indirectly from the Relay 109 (I don't have my schematics here.).
 

DudaEnergy

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2003 VW 1.9L
I agree. If the power is coming from the ECU then it is not a good idea to draw more from it. I'm surprised the ECU would directly power a solenoid valve anyway. I'm hoping to find a schematic of the wiring so I can tell what's going on and find a new source to power the lift pump.

I did fire up my wife's car and confirmed a sudden spike of 60v to the fuel shutoff valve and then it quickly dropped to 0v.I'd say within 1 second because I only saw maybe 0.05v as the next number after 60 disappeared. I can only assume my car does the same but I didn't test it. It's baffling to me as to how that solenoid stays open with no sign of it being energized. Is it used to stop the engine or is it used as some kind of safety for when the engine is off?

I'm still waiting for idparts to get back to me about their wiring instructions. For my next drive, I will give 12v power to only the lift pump and see if the car has any problems. If the fuel sending unit was the problem then I shouldn't notice any issues. It baffles me how so many people have put on lift pumps with those instructions but this issue didn't come up / the instructions still exist.

The other interesting thing is I've seen information elsewhere (youtube videos) about power failing to open the fuel shutoff valve and inability to start. And the guy fixed it by applying 12v directly from the battery. I think he claimed it was due to a faulty relay 109. But as I've learned, relay109 supplies power to a lot of things. I don't think the car can still start without relay109, can it? Or maybe putting power to the fuel shutoff sends the 12v to all the other places that are supposed to get it from 109?

My car did start without the battery power hooked up (probably running off what's in the fuel filter because without the lift pump powered, it can't get fuel from the tank) so I believe that means relay109 is working as well. I've thrown out the possibility that maybe I put the new relay109 in the wrong way simply because the car can start.
 

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
The Solenoid Fuel Shut-off Valve's purpose is to shut-off the fuel as it's name implies. However, it must open for the engine to start. There is a very weak spring that keeps the plunger pushed out (off position, I assume). It may be possible that the coil inside the valve operates on extremely low voltage. You can take a perfectly running ALH engine and remove the Shut-off valve wire and it will not start!

The Relay 109 is "the" relay that powers all the things, including the ECU, that allows the engine to run........ I mean everything associated with fuel management, various temperature sensors, air flow sensor, boost sensor, ECU input, accelerator pedal, cruise, operation of the Turbo boost mechanism(s), etc., receives power from the Relay 109. Relay 109 does not directly provide power to the Glow Plugs. That is a function of the ECU through a separate Relay (two relays depending the model). I've been through these schematics hundreds of times doing my ALH conversion in the 84 Vanagon.

To make things a little muddy, the ignition activates a part of the ECU which in turn activates the 109 Relay which in turn energizes all those things I mentioned above as well as the balance of the ECU through pins 1 & 2, if I remember correctly!

Connecting 12 volts directly from the battery to the Shut-off Solenoid Valve while leaving it's wire connected, will back-feed current to the hot side of the 109 Relay (down stream, if that makes sense), thus, making one think that an otherwise bad relay is in fact good. This will power up all those things that the Relay normally supplies power to as I mentioned above.

As I stated in the other post, other than the one connector that I referenced, the circuit from the Fuel Shut-off Valve goes directly to the ECU. It is not fused. I do not know of any schematics for the internals of the ECU.

The Relay 109 will only plug one way!
 

p377y7h33f

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Brooklyn
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2003 Jetta Wagon 5-Speed in Tornado Red
Quick question, is fuel supposed to flow if the plunger is removed from the N109 solenoid and it's screwed back into the pump "empty"? I just replaced a head seal on the IP, but nothing comes out the injector lines. Primed the filter, primed the pump, but it's as if the N109 is cutting off the flow to the injector lines.
 
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Mongler98

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98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
Just because you replace a relay, does not mean the socket for the relay is not bad or the replacement relay is not good.

go back to that relay. its not like this just had another cause right? keep working and tracing that relay, and i promise you will find your issue. Might be a broken wire in the dash, the wires in these 20 year old cars get a bit brittle in some places like in the door accordions. Stop fiddling with the solenoid and get back into the dash area with a multimeter on that relay socket and trace this issue back.
I replaced my 109, had the same issue, turns out one of the clips (metal bit in the socket for the relay) was corroded some how and had worked its way back about half way out of the socket. I would have to wiggle it every few weeks to get it to start, then it got worse.

go back to your 109 and figure it out. 99% sure your problem is there and you have not fixed it yet.
good luck.
 

AndyBees

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Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
p377y7h33f, if you left the plunger out, then the Shut-off Valve is "crippled" and cannot perform it's intended function! Thus, there must be other problems with your injection pump!

Did you remove the Injector cover, etc., to replace those seals?

As for the OPs issue, I agree with Mongler98, go back to the Relay 109 Socket and do a good inspection there!
 

KLXD

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Aug 22, 2009
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Lompoc, CA
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'98, '2 Jettas
Pulling the guts out will not keep the engine from shutting off. The ECU sets the IQ to zero when you turn off the so it'll still kill the engine.

The solenoid valve was the only cutoff on the mechanical pumps but is redundant on TDI's.

That's not to say I think that removing the plunger will fix your problem.

You should bring this up in your thread on the head seal and in it answer Andy's question about the QA seals.
 
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KLXD

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'98, '2 Jettas
I did fire up my wife's car and confirmed a sudden spike of 60v to the fuel shutoff valve and then it quickly dropped to 0v.I'd say within 1 second because I only saw maybe 0.05v as the next number after 60 disappeared. I can only assume my car does the same but I didn't test it. It's baffling to me as to how that solenoid stays open with no sign of it being energized. Is it used to stop the engine or is it used as some kind of safety for when the engine is off?
Your post has me wondering. When you say "fire up" do you mean start the engine? I ask because I was sure the voltage at the solenoid on the running engine does not stay at zero.

To verify I just checked my '98. Turn key on and it has battery voltage for about 5 seconds then drops out. Turn key to start and I get alternator voltage. Engine starts too fast to try to read voltage during cranking but there's no reason to believe the power to it stays off or it wouldn't start.

I have no reason to believe the ALH behaves any differently. It's not home or I would have checked it too.

So, if my understanding of your use of "fire up" is correct you may have a problem with your meter. If you are just turning on the key then it's behaving normally.

Maybe others are correct and the ECU is not capable of energizing your relay and also properly powering up the things it's supposed to but I wouldn't think ID Parts would recommend it if it caused problems.


Maybe some background on your issues is in order. Why did you install the electric pump?
 
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Matt-98AHU

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2001 Golf TDI, 2005 Passat wagon, 2004 Touareg V10.
Not saying this is your issue, but I have had two ALHs with strange, similar symptoms.

They would give the shut off solenoid VERY brief 9V, like sub 1 second, and then shut it off. Normally they get 12V for about 3 seconds before the ECU cuts it off if you haven't attempted to start it.

Both were missing a fuse or it had blown. But it's very bizarre how the ECU still comes on at all considering what fuse it is.

It's fuse 32 on the side of the dash. That fuse powers the quantity adjuster along with pins 1 and 2 at the engine computer. You'd think the engine computer doesn't come on at all, but somehow with that fuse removed, electricity is BACKFED from the quantity adjuster to the ECU... but less voltage than normal. It's a voltage drop of about 3V compared to battery voltage (about 9.5V instead of 12.5V measured at the battery with a healthy battery for example).

It's just enough to turn the engine computer on, but the moment you attempt to start it, the voltage drops low enough to just simply shut the computer off altogether. And you will see the check engine light and glow plug light turn on and off repeatedly while you crank the engine as voltage goes up and down during cranking.

One car, the owner had removed the fuse for some inexplicable reason and never reinstalled it in the right spot. The other car the fuse was simply the incorrect size (10 A instead of 30 A) and had blown.

So, I guess whatever internal circuit in the ECU that is on the opposing side to the power in for the QA (ECU pins 116 and 121 splice together and then wire to pin 6 at injection pump, power from fuse 32 comes in at pin 5 at injection pump and the wiring diagram indicates they are the two opposing sides to the quantity adjuster. Maybe the ECU supplies counter voltage instead of ground to get the QA to a resting state when the engine isn't running? Then starts duty cycle switching ground when it does want to move it?) is getting voltage from the lone wire that is from terminal 15 (ignition switch power via fuse 29 to ECU pin 37).

Not saying that this is your issue, but it is a possibility. Take a close look at fuse 32 on the side of your dash.
 

DudaEnergy

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May 4, 2015
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Madison, AL
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2003 VW 1.9L
To give an update and answer questions that came up:

Yes, fire up means starting the car. My wife's car showed zero volts when running and it was fine.

I removed the hot wire that was powering the fuel solenoid valve and just ran the lift pump directly from the battery instead. I have no problems. Car starts, I can romp on it on the interstate. It is clear that there is no problem with the fuel shutoff valve. SO no, my relay109 is good since I'm not feeding 12v back to anything. And all of this makes sense because of the restrictive fuel sending unit I had.

I am still confused as to why voltage drops to zero but it was mentioned that they are not even needed for the TDIs so maybe these valves use assisted pressure and do not actually close until the fuel stops flowing. Wild guess. I could test it by checking the voltage while the car is cranking but not able to get fuel. I suppose I could also test it by pulling the wire off the fuel shutoff once it's running to see if it kills it.

IDparts has not responded to my email. I might try calling in case they didn't get it. But at this point I think their instructions are just wrong.

Now, I am still hooking up my lift pump manually each day. Anyone have a recommendation on where I should get the power from for this thing?

Also, the instructions said I could put the fuse box cover right back on but apparently it doesn't fit for the 2003 because it didn't expect a new relay in the empty slot. ANy clue if the fuse boxes were different for older models? One post somewhere said this lift pump "doesn't work" for the 2003 so I'm thinking that minor detail might be the issue.

I also haven't bothered to attack my power leak. I'm just pulling the battery wire every night. I'll be checking the car audio stuff first to see if those are the cause. Otherwise, I'm going to be chasing wires forever if the installer crossed a wire or something that caused something to always be powered on. We can't pull fuses on this thing to see where the drain comes from? Checking resistance on the fuses is a huge PITA.
 

KLXD

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Aug 22, 2009
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Lompoc, CA
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'98, '2 Jettas
Some comments/questions:
To give an update and answer questions that came up:
Yes, fire up means starting the car. My wife's car showed zero volts when running and it was fine. I don't get it, engine shouldn't run.

I removed the hot wire that was powering the fuel solenoid valve and just ran the lift pump directly from the battery instead. I have no problems. Car starts, I can romp on it on the interstate. It is clear that there is no problem with the fuel shutoff valve. SO no, my relay109 is good since I'm not feeding 12v back to anything. And all of this makes sense because of the restrictive fuel sending unit I had. Had? Did you replace it or just add the pump?

I am still confused as to why voltage drops to zero but it was mentioned that they are not even needed for the TDIs so maybe these valves use assisted pressure and do not actually close until the fuel stops flowing. Wild guess. I could test it by checking the voltage while the car is cranking but not able to get fuel. I suppose I could also test it by pulling the wire off the fuel shutoff once it's running to see if it kills it. They are not needed to shut off the engine. They need to be energized for it to run.

IDparts has not responded to my email. I might try calling in case they didn't get it. But at this point I think their instructions are just wrong.
Now, I am still hooking up my lift pump manually each day. Anyone have a recommendation on where I should get the power from for this thing?

Also, the instructions said I could put the fuse box cover right back on but apparently it doesn't fit for the 2003 because it didn't expect a new relay in the empty slot. ANy clue if the fuse boxes were different for older models? One post somewhere said this lift pump "doesn't work" for the 2003 so I'm thinking that minor detail might be the issue.

I also haven't bothered to attack my power leak. I'm just pulling the battery wire every night. I'll be checking the car audio stuff first to see if those are the cause. Otherwise, I'm going to be chasing wires forever if the installer crossed a wire or something that caused something to always be powered on. We can't pull fuses on this thing to see where the drain comes from? Checking resistance on the fuses is a huge PITA.I wouldn't expect a .5 amp load to kill a good battery overnight.
 

DudaEnergy

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May 4, 2015
Location
Madison, AL
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2003 VW 1.9L
Some comments/questions:
Well, it runs as well as my wife's car and 2 others on here. It drops to zero volts after the initial kick on. And as I stated before, if not attached to the fuel shutoff, balances to a constant 5v. It's weird. I don't think it would power the relay directly. it certainly doesn't with the key turned. I doubt it with the car on.

I added a pump. The fuel sending unit contains a check valve which must have been blocked up and causing the extremely slow flow of fuel. Thus, romping on the accelerator gave symptoms of lack of fuel. I put the pump to help it out/replace the fuel sender and let me do more things in the future.

The battery was originally fine for a while. But if I didn't run the car for a few days, the voltage drop was evident. And now i'm at the point (months later) where it's dropping to 10v or so if it sits most of the day and all night. 0.5A draw is pretty bad. I'm not going to ignore it as if it's anywhere near normal.
 

Matt-98AHU

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And now i'm at the point (months later) where it's dropping to 10v or so if it sits most of the day and all night. 0.5A draw is pretty bad. I'm not going to ignore it as if it's anywhere near normal.
No, half an amp is definitely not anywhere near normal. Not surprised that drains overnight.

On more modern cars, VW's acceptable draw limit is 0.030 A. Most Mk4s if everything is correct will often be less than half of that. And it normally does not take them long to go fully to sleep.

A very common range of amp draw I see on mk4s is 0.011-0.015 A if they have no issue.

I have seen a variety of things cause draws, but usually only a couple tenths, not a whole half amp. Window motors/door control module, the radio, broken data bus wires between a door and chassis shorting out and some of the biggest parasitic amp draws I've seen have come from alternators that were somehow internally shorting.
 

DudaEnergy

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Madison, AL
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2003 VW 1.9L
I got my lift pump hooked up finally. I found a 12v ignition power source running relay53 which is always consistent so I tapped into that to run the relay for the lift pump. During testing of the relay and all that fun stuff, I measured something like 15.2 VDC on the battery while it was running. Seems a little high and odd because my dash display (for the performance stuff) maxes out at 14.4 VDC when I'm driving. So I don't know which one is wrong.

I'm still getting the amp drain. 0.33A going to the main wire that powers the car and 0.27A going to the wire that runs all the amps in the back. I disconnected the breakers for each amp and it still draws the same. So I disconnected the main breaker running that wire and of course, 0 draw now. I have a hybrid capacitor in the back so whatever device was eating the power should still draw from that battery but I found nothing when checking each and every wire connected to it. So I'm pretty clueless as to where that power was going.

I'm keeping the two batteries disconnected for now to watch how each one drains. The hybrid capacitor has less capacity than the battery does so if there is a drain I should see that voltage drop relative to the main battery overnight. I suppose it's possible that the drain going to the audio equipment could be that hybrid capacitor if it's dying or dead. It would suck away power from the battery in that case and that's the only thing which would make sense at this point. But 0.27A running through the main wire to the car electronics is still a concern since those are unrelated toe the hybrid battery, especially with the two being disconnected now and no change to that power draw.
 

DudaEnergy

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2003 VW 1.9L
A thought occurs. I think the amp device I'm using is only good for AC current and not DC current. So I'm going to get the right device for checking the DC current drain to be certain of my reads. And if I'm right that maybe the hybrid battery is shot, that could be what's actually draining my battery. Got my fingers crossed that I'm right because replacing that hybrid battery is expensive but certainly way better than efforts climbing through the wiring to find some random and unknown power leak.
 

DudaEnergy

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2003 VW 1.9L
This is it: https://www.mouser.com/ProductDetail/Maxwell-Technologies/BMOD0500-P016-B02/?qs=JV7lzlMm3yLb3EfliaQ9qw%3D%3D&gclid=CjwKCAjw7tfVBRB0EiwAiSYGM8KyHd0_avVF--VTcrWhIXI8FXTnP0dzwei8sGgGLenCV8qGDtw9WBoCNdgQAvD_BwE

It's been a while since I had researched these things. I bought it back in 2014 and didn't get my car audio in until 2017. So I believe "hybrid" is not correct. It's a "Super Capacitor." I believe I had hybrid stuck in my head because it is some sort of capacitor / battery combo. If it were a straight capacitor, no way in hell would you get 500 Farads with something this small.

It is there to help balance out the power needed as my 3000 watt system thuds in the back of this wagon. I also have an over-sized power cell as the battery in the front with an 0000 gauge wire running to the back and hooking the ultra capacitor up to the main system so there's no doubt voltage drops are as low as possible.

Even more fun to this set-up is I have an external rectifier tapped into the alternator. There is actually AC power running directly from the alternator to my trunk where this rectifier then converts it to DC and feeds to the ultra capacitor. This is supposed to help take a load off the rectifier in the alternator so it won't burn out but as an added bonus, I'm now running higher AC voltage to the back for less loss of power to power the system. So about 50% of the power comes from the alternator rectifier and travels to the power cell then through the quad wire to the ultra capacitor and the other 50% goes right to the trunk through the external rectifier and powers the ultra capacitor there. It's worked very well. I still hold 14 volts even when the system is slamming hard enough to vibrate my side mirrors to where I can't see anything. Wagons are very good for subs.

So I did use the correct multimeter this time to check the amps. I got a 0.2A draw going to the back of the car. And then was stupid and blew the fuses in it trying to check the voltage of the battery while it was still hooked up for amp checking. So I need to get fuses before I can see if the root of the problem is that ultra cap. I am pretty much 90% sure it is because I did let it drain to zero and sit for a few years. When I first charged it up it seemed fine but with it not being a true capacitor I think it's likely worn out a bit and causing this amp drain. I'll know for sure after letting it sit overnight and see if it has significant voltage drops. Then I can try the same by killing the breakers to the amps for a night and see if it still dies on its own. That'll give me a clue if it's the capacitor itself or the equipment. I doubt it's the equipment since the amps are not powered when the car is off.
 

DudaEnergy

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2003 VW 1.9L
Yup... you've got to go out of the way a bit (and spend a bit more) to get one that can do DC amps... very different sensor within the meter.
Actually, the AC ammeter is the more expensive multimeter. I just forgot you can't clamp DC cables to get amps like you can with AC. So I got out my cheap craftsman multimeter and tested it to find one amp rating and then blew the fuses forgetting to hook it up right to check voltage. Essentially I shorted the battery terminals together so I'm glad there are fuses lol
 

Vince Waldon

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Well, I was thinking you *were* referring to the clamp-on variety. :)

The AC version is just a simple current transformer as a clamp, whereas the DC clamp version needs a Hall Effect transducer and more internal circuitry.

Cheapo current clamp meters from Harbour Fraught are almost always only capable of AC current, but spend a bit more and you can get DC amps in a clamp-on too. :)

Whatever works. :)

Back on the subject at hand, if you're looking for accurate in-place current readings the official VW TSB on current drains just uses a DMM in millivolt mode and leaves everything connected... so no rogue current drains from modules waking up.
 

DudaEnergy

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2003 VW 1.9L
I have a Klein CL700. When I looked it up, I realized it stated AC but nothing about DC for the amperage. So then I used my cheapo multimeter and blew the fuses. At least I found out about the 0.2A draw going to the audio equipment. And I also realized the Klein device is defective, as it wouldn't read voltages on the battery. So I have another one on order. I'll have to look for one that can do DC too as that would be ideal.

So my experiment failed. Today both the battery and the capacitor read 10.5 volts. So then I checked continuity and found out there's a weak signal sometimes going through the 300A breaker. Then hooked up the battery terminals to charge and that showed voltage to both units even when continuity couldn't be found from unhinging the breaker until no continuity reading. I then detached the wire going to the back from the breaker and finally got 2 different readings between the battery and the capacitor.

So I have a defective breaker. The capacitor on its own reads 15 VDC just from the short charge I gave the system. I'm charging the battery now to get it back up to 12 VDC. Then I'll leave the 2 disconnected for another day's time with that lovely live wire just hanging there under the hood and check again tomorrow to see which one of them is dropping and know at least which side of the system is the culprit.

I'll pick up some fuses soon to start checking the amps again once I know where I should be looking. And with a working Klein multimeter I should be able to check voltage drop on fuses if the drain is on the battery side. Although at this point it could be the battery that's dying now because of all of the drains it's gone through. It is a power cell but I don't know how long it would hold up.

I'll have to find a clamp device that can check DC current. That would be way easier if I have to start checking every single wire I have in the back.
 

DudaEnergy

Well-known member
Joined
May 4, 2015
Location
Madison, AL
TDI
2003 VW 1.9L
Looks like the Klein CL800 does DC amps. This what I get for buying this thing from Home Depot. I'm an avid online shopper and almost always get screwed when I go to a brick and mortar store due to time constraints. We deal with a lot of high voltage / current in our warehouse and I'm pretty sure I grabbed the best one they had on the shelf. Oh well.
 

DudaEnergy

Well-known member
Joined
May 4, 2015
Location
Madison, AL
TDI
2003 VW 1.9L
With the audio equipment in the back separated form the main system, the Battery drained to 10v overnight, capacitor held solid at 14.9v. Then I disconnected the battery from the system and let the capacitor stay connected to it only for a few hours. Drained it down to 10v. So this has proven that the audio equipment in the back isn't drawing anything (no draw from the cap the first time) and the car itself is draining power at a hellish amount (drained the cap when connected to car electronics).

I'll start checking amps over wires to see exactly where it's going tomorrow. Then check milivolts across fuses etc... I'm probably going to bring this back to the car audio guys since the problem started after the install. They must have screwed something up in their wiring.
 

DudaEnergy

Well-known member
Joined
May 4, 2015
Location
Madison, AL
TDI
2003 VW 1.9L
I have a lead to the issue of the power drain. Lately I noticed there's a humming/buzzing sound in the engine compartment that goes away when power to the car is disconnected.Using a stethoscope, I found the buzzing sound is greatest on/in the alternator. But it can be heard all throughout the engine.It makes no sense though as I've disconnected all wires to the alternator including the plug and it's still buzzing. Has anyone ever heard of some sort of power drain, whether it be a exposed wire or something feeding electricity through the whole engine and causing a vibrating noise like this which is most audible from the alternator? I can't see how it would buzz with nothing connected to it other than the frame.
 
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