2002 Golf - I'm back in a TDI!

[spifflifkin]

I did some Googling over break and found a few things to look in to.

There is a TSB from VW regarding parasitic drain: https://pics.tdiclub.com/data/500/TSB_27_08_04_Matrix.pdf

In VWVortex there is a thread about aftermarket radios not turning off the Monsoon Amp. https://www.vwvortex.com/threads/mk...ion-and-modifications.9487666/#post-115282118
I installed a new aftermarket radio recently. There was an after market one in there when I got the car. With the new radio I had Crutchfield make an adapter harness. One interesting note is that the power to the radio I took out was run to a switched fuse on the fuse panel. The new radio gets power through the wiring harness.

I'll check with our electrical guy here to see if he has a current clamp.

 

[P2B]

Our wagon had a dead battery once because one of the courtesy lights above the rear doors got bumped on while loading cargo - those lights always have power and are easily overlooked.

 

[csstevej]

Do you have an amp meter hooked up and set to milliamperes? What are you seeing ?

 

[spifflifkin]

After the car sat locked all day I checked all the fuses, including the ones under the hood. Lots initially had voltage, but quickly dropped to 0.

I found a current clamp. On the negative of the battery it read .35A. I'm suspect of that measurement because the meter crept back to .35A when it was not being used... I think I didn't zero it correctly. I'll redo this test tomorrow.

 

[spifflifkin]

Do you have an amp meter hooked up and set to milliamperes? What are you seeing ?

I'm suspicious that I may have left a door not fully closed and didn't notice. I'll be more careful in the future to make sure that I hear the beep when I lock it. The rear driver door latch is bad. I can leave that door open and the alarm will beep. I'll replace that in the next couple weeks.

 

[spifflifkin]

Do you have an amp meter hooked up and set to milliamperes? What are you seeing ?

I have a Fluke 177. It can measure current draw. What tests would you recommend?

 

[csstevej]

I didn’t have the clamp on version of an amp meter so I had to put the meter in series with the battery.
If you’re reading .35 amps that’s high that equals 350 milliamperes.
If you’re still reading this value after 30 minutes with everything closed I’d start pulling fuses one at a time and see which fuse drops it drastically.
Then I’d pull up wiring diagrams for that circuit and see what’s on it.
That’s how I found a parasite drain on my Silverado.
I accidentally installed a power wire for my plow to a constant power circuit. Even with the plow off it was still powered and killed the battery in 5 days….. it was pulling .45 amps - 450 milliamperes.
Drove me nuts looking for it as it didn’t happen when the plow was disconnected and stored on the side , only after the first year did it pop up.

But using that video helped me to find my mistake.

 

[spifflifkin]

@csstevej
Gotcha! I have it pulled in to the shop now with the driver door and the hood open (latches closed so the car thinks they're closed) and the car locked.
I'll let it sit for a couple hours then check again. Good idea pulling fuses to see when the current draw drops. I will report back with my findings later today.

 

[spifflifkin]

When I zero the current clamp it shows .4A draw. When I don't zero it, it shows .02-.03A. According to the VW TSB the max deep sleep current draw is 30mA*. I need to test that thing on a known current.

I double checked all the fuses and all dripped to 0V quickly.

*Edit: I originally 50mA as the max current draw. @Matt-98AHU pointed out that it should be 30mA

 

[spifflifkin]

Got new hub caps! They are from AutoWheelCapLed
$24.00 + $12 shipping per set. I got 2 sets. It was $72.00 including shipping. They arrived in about 2 weeks.

 

[Matt-98AHU]

When I zero the current clamp it shows .4A draw. When I don't zero it, it shows .02-.03A. According to the VW TSB the max deep sleep current draw is 50mA. I need to test that thing on a known current.

I double checked all the fuses and all dripped to 0V quickly.

50 mA should be max allowed draw for a Phaeton or Touareg of the mid 2000s.

Every other model is a max of 30 mA. And most Mk4s that have zero issues in my experience are more like 11-15 mA draw when everything goes to sleep... And that's with me using my Fluke 88V inline with the battery ground cable measuring amps, not one of those unreliable clamp setups that can't get you such low readings very accurately.

Now, when checking fuses on the side of the dash, *some* of them should be hot at all times. Some are terminal 30, which never turn off.

Also don't forget there are a couple 15 A fuses above the RELAY panel under the dash. Not as easy to see or get to. Some panel removal is required.

The milliVOLT drop measurement method is very good for quickly narrowing down where draws are on fuses without having to pull them. Exactly how the video describes.

Also, alternators can cause very large draws that can bring down a battery overnight.

Head units can certainly cause draws,

Monsoon amps can cause draws on their own.

I've had a lot of weird CCM system related draws. Sometimes from someone swapping a used window motor of the incorrect convenience system generation. Sometimes from a corroded or broken CAN bus wire in the system somewhere. I've had numerous original VW radios make the CCM system think the HOOD is always open. The "alarm" wire at the radio is wired to the same circuit as the hood latch switch. So if the radio was removed, before it gets unplugged it's actually designed to short ground to that wire, making the system think the hood suddenly was opened and thus setting off the alarm on a car that was locked and armed (if someone broke the window, did not open the door and attempted to remove the radio sort of idea...).

I've just removed that wire from the connector at the back of the radio on a number of cars to prevent it from thinking the hood was open when it wasn't.

A combination of knowing where to use the scan tool to look at certain things plus. knowing where *all* the fuses are and having the tools to measure can pretty quickly narrow down where the problem actually is.

 

[spifflifkin]

Every other model is a max of 30 mA.

Oops. I read the TSB wrong. You're correct.

And that's with me using my Fluke 88V inline with the battery ground cable measuring amps,

Ah, cool. I just go buy one of those... wait, never mind. LOL That's serious multimeter! I have a Fluke 177. I wonder if that would work.

Now, when checking fuses on the side of the dash, *some* of them should be hot at all times. Some are terminal 30, which never turn off.

I did see that some were always hot.

Also don't forget there are a couple 15 A fuses above the RELAY panel under the dash.

I didn't know about these.

I'm a little spooked about electrical problems. In my 2003 Jetta I bought new then sold in 2008, no electronics would turn on when the car stared some times. No lights, gauges, windows, nothing. I'd have to turn it off and restart it several times until the electronics started working. I ended up selling it because of that.

I'll let it sit and see if it goes dead again. If it does I might need to come down and visit you again!

Thanks for the tips!

 

[Zak99b5]

Ni

Got new hub caps! They are from AutoWheelCapLed
$24.00 + $12 shipping per set. I got 2 sets. It was $72.00 including shipping. They arrived in about 2 weeks.

nice find. I’ve only seen them for $35 or so EACH. I know what I’m getting my son for his birthday lol.

 

[spifflifkin]

It looks like the battery is losing about .20V every 12 hours.

Once the engine was installed during the rebuild I left the battery hooked up most of the time. I don't remember the voltage dropping this much. It would sit for days without being started. It always fired right up.

Since then, I've changed the head unit (adapter harness made by Crutchfield), added the scan gauge, changed both front door latches. Other than that, I can't remember any electrical changes.

Scan Gauge II: https://www.scangauge.com/products/scangauge-ii/
Head unit: https://www.crutchfield.com/p_113KMBT732/Kenwood-KMM-BT732HD.html
Driver: https://www.idparts.com/door-lock-module-front-left-oes-a4b55-3b1837015as-p-16478.html
Passenger: https://www.idparts.com/door-lock-module-front-right-a4b55-3b1837016cf-v10-0012-p-1925.html

I unplugged the Scan Gauge this morning after driving it to work. I'll check the voltage after work, after driving it home, then in the morning.
Next I'll unplug the head unit and repeat the voltage checks.

 

[csstevej]

Scan gauge won’t cause it.
Head unit might.
Yeah you have a parasitic drain going on.

 

[spifflifkin]

3/31
6:00pm 12.02V Sitting for ~16 hours after driving for ~1 hour.
4/1
7:00am 11.84V
7:30am 12.48V after driving to work (20 min).
12:30pm 12.15V - unplugged head unit.
3:00pm 12.06V
5:00pm 12.0V
6:00pm 12.51V after driving home - unplugged Amp
8:00pm 12.32V
4/2
7:00am 11.98V
7:30am 12.38V after driving to work (20 min) - Unplugged dash cam
3:30pm 12.01V


This is the harness Crutchfield made.


This is the NAV module in that harness: https://www.crutchfield.com/p_1209003NAV/Axxess-XSVI-9003-NAV-Wiring-Interface.html
" Connect a new stereo and retain RAP and factory amp in select Volkswagen vehicles "

 

[spifflifkin]

Is this a legit current draw test setup?

The multi meter is connected to the ground terminal on the battery and to the battery cable.

I've done the fuse voltage test a couple of times. I checked the 2 under the dash too. They all read 0.

I bought a new battery last night an still see voltage drop overnight.

I turned the light on the meter on every 10 minutes to keep it awake for several hours. The current draw didn't change at all. When I pull all 3 of those fuses it drops to 0. But if I connect some of the other cables to that fuse box, the current draw jumps to about .33A...

I'm lost on what to do. But I'm not going to give up!

 

[csstevej]

If it’s in series with one of the battery cables then yes. I see the ground battery cable….but don’t see anything connected to it.
The connection to the battery I see the black lead clamped to the negative post that’s good……just dont see where you have the positive lead.
If it’s to a ground source then you’re correct.
Is everything is closed , or latched in the closed position and at least 30 minutes have passed to put the modules to sleep and your see that when set to milliampere ……then yes that reading is correct and it’s too high……
Start pulling fuses one at a time in the fuse block and see which one drops significantly, put back the ones that have no real effect.
Leave everything connected except the battery cable you have the meter connected too.
That’s the circuit you need to look into…..

 

[spifflifkin]

@csstevej

Thanks for the tips! I did check all the fuses including the two under the dash. I put the car in the shop opened the driver's door and the hood and activated both latches of the car thinks the doors and hood are closed an armed it. I let it sit for about 4 hours until lunch and then tested the fuses. They all were zero.

Here's a better picture with my fluke hooked up.



Edit: replaced the picture with the one that has the meter hooked up correctly.

 

[csstevej]

It’s not the fuses that you need to check , it’s when you pull the fuse you’re looking for the milliamperes to drop on the meter. Has nothing to do with voltage drop or power across the fuses….. something is draining power.
When you pull the fuse to the problem circuit the current will drop . Then somewhere in that circuit is you issue.

 

[spifflifkin]

Oops. That's what I meant to say I did today. I pulled each fuse one by one and watch the meter. It didn't budge.

I will try again tonight. I've had the car sitting awhile.

 

[spifflifkin]

Check this out!!! The current drops quite a bit when I disconnect the alternator wire. It's a brand new alternator from Napa. Wonder if it's the cable?

@Matt-98AHU "Also, alternators can cause very large draws that can bring down a battery overnight."

Looks like it might have something to do with the alternator Matt thanks for the tip!

 

[J_dude]

I've heard of these alternators causing battery drain before, not sure if new ones would though.. @Mozambiquer?

 

[spifflifkin]

@csstevej
I went through pulling the fuses and paid more attention this time. Fuse number 42, the amp/radio is pulling about 30 mA!
With the alternator disconnected in the fuse 42 pulled out the current draw is about 15 mA now!

 

[P2B]

So the alternator is drawing around 355mA (400 - 30 - 15)? If so it's defective, take it back to NAPA.

The head unit drawing 30mA is not ideal, but it would take a few days to kill a fully charged battery.

 

[Mozambiquer]

Check this out!!! The current drops quite a bit when I disconnect the alternator wire. It's a brand new alternator from Napa. Wonder if it's the cable?

@Matt-98AHU "Also, alternators can cause very large draws that can bring down a battery overnight."

Looks like it might have something to do with the alternator Matt thanks for the tip!

Check and make sure you don't have constant 12v power to the L pin on the alternator plug, or you can also simply pull the alternator plug and see if it drops, since the alternator L terminal should only have power with the key on. I've seen some people hook that up to battery power to fix a no charge issue, but it will constantly have the regulator trying to make the alternator charge and cause a bad drain.
The other issue can be if the rectifier is failed, which isn't very common on those Bosch alternators, but I have seen it on the parts store ones.
If that is the case, I would take it back for a refund and get an oem alternator, or, not to toot my own horn, but I've also got alternators which I remanufacture with all OEM components along with new oem ones.

 

[spifflifkin]

Check and make sure you don't have constant 12v power to the L pin on the alternator plug, or you can also simply pull the alternator plug and see if it drops, since the alternator L terminal should only have power with the key on. I've seen some people hook that up to battery power to fix a no charge issue, but it will constantly have the regulator trying to make the alternator charge and cause a bad drain.

Thank you for the tip! I will check this tomorrow night then report back.

 

[csstevej]

Nice , at least you’re heading in the right direction.
If it is a bad alt I highly recommend one from Moz…. He does an excellent job on rebuilding them.

 

[pudman2003]

This is what I use to identify current draw.
For the electronically challenged.
Follow the current Draw!

GTC CM100 CLAMP METER

 

[pudman2003]

I'M very challenged!