Dead accelerator pedal, ALH

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
The ALH in my Vanagon.

This past Sunday evening at about sunset, while cruising at 65 (cruise on), AC on, lights on, raining, and wipers on, a road side warning light began flashing indicating that the upcoming traffic light was about to turn Red. I tapped the brake pedal to kick-out the cruise. Then, as I pushed the accelerator for a bit more power it was dead.

I managed to get the Van into a parking lot... had to have it towed.

This evening, I plugged in an accelerator pedal from my stash. Presto, problem solved..... sort of!

So, here's the questions.

- Does the accelerator operate on 12 volts or something less?
- Can the accelerator be tested/repaired/rebuilt?

There have been several P0226 DTCs to appear scattered back over the years and miles. But, not one of them resulted in a no go situation. I have always deleted the code and drove on. That code pertains to the accelerator.

So, was the accelerator going bad all along or was there a power surge? Did something with the cruise cause the issue or maybe the OBD port circuits. The OBD was operating as I scanned and deleted the code numerous times with no good results.

I ask those questions because from time to time the OBD port has gone dead for a little while... just thought it was the Scan Gauge acting up. And, about three weeks ago I repaired the circuits at the stalk on the cruise control. The cruise has worked flawlessly since I repaired (over 1000 miles and was working when this incident took place).

Is this just a bunch of electrical gremlins I need to sort out? I sure hate to destroy another accelerator and pay $155.00 to be towed.

Thoughts!
 

WildChild80

Veteran Member
Joined
May 30, 2016
Location
Nashville, AR
TDI
2001 Jetta TDI 2000 Jetta TDI 2000 New Beetle TDI ALL 5 speeds
Was there any possibility of the pedal plug getting wet? I had just the smallest amount of water in my pedal and it went bonkers, this was on the day I was embarking on a 1200 mile trip...

Sent from my Pixel XL using Tapatalk
 

Fahrvegnugen

Veteran Member
Joined
Jan 21, 2017
Location
Burlington Vt
TDI
01 golf 1.9 alh gls silver
My thought too, since it was raining. If you couldn’t have been towed, maybe it would’ve worked again once dried out. Its better to have another working one in!
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Nope! Dry as a bone! Nothing wet anywhere in that area or on the pedal. I did have a good light and looked at both the brake connector and accelerator pedal.

Over the last few hours, I've been looking at schematics. There's nothing that sticks out like a sore thumb. So, I'll just have to check all splices and connectors.

Oh, my entire electrical wiring "mess" is inside conduit under the Van and comes up through sealed holes on both ends.





 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Happens all the time! Mine got wet and freaked out. Ended up replacing this TPS:

http://forums.tdiclub.com/showthread.php?t=253512

Well, after reading through that Thread, I'm pretty much convinced that the TPS is the issue, water or not!

Wow! And, just think, we've driven this Van to Alaska two times..... lots of rough back roads, rain, heat, cool, etc. And, all the while I had two extra pedals hanging on the wall in my garage!
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
I thought limp mode for a bad pedal sensor was a high idle???

Idunno where I read that. Prolly here.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Okay, problem solved by installing a known good accelerator pedal.

Yeah, my engine went to a high idle, just under 1100 RPMs. I could clear the code and the idle would drop back to 903 RPMs but still no response from the accelerator. Then, if I cut the engine off and restarted, idle would be normal until I pressed on the accelerator.. then back to something under 1100 RPMs.
 

csstevej

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Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
Andy , Is this wired like the A-IV platform when you step on the brake pedal and it disables the accelerator?
Just a thought?
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Csstevej, yep, I set it up just like it came out of the 02 Jetta, both clutch switches and the double brake switch.

And, yes, I've been getting the Brake Switch Code because the stop I set-up to cut-off the switch has not been the best. And, even with an extra spring, the brake pedal doesn't always come back solid. I've shimmed the stop with felt to add extra pressure. Also, in 2013, I took out the brake assembly and buffed the big cross pin, greased and re-installed. Guess I need to re-visit it again.

Anyway, when I've had issues with the brake switch, it was just a matter of pulling up on the pedal with my shoe toe and/or clearing the DTC.

But, during this incident, there was never a DTC for the brake switch.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
As far as I can tell it connects into the ECU.
No direct power unless it's from the ECU.
it runs off 5v reference for the two TPS sensors, the 'kickdown switch' I'm not certain about, but it'd make sense for it to use the same 5V
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, again this afternoon, lost use of the accelerator pedal.

Without all the boring details, the Brake Switch code come back too. BS = flashing GP light ad the dead or inoperable accelerator is a CEL, of course, both have codes.

Deleting "codes" with the Scan Gauge out on the road isn't always helpful. Scan Gauge doesn't always read/reflect the DTC for the inoperable brake switch.

Anyway, although I did have a new (used to me) accelerator pedal to function a few days ago, I believe there is a "connection" to the bad brake switch intermitting failures. I do know if the brake switch cruise side is open, the accelerator will not function. Seems I read somewhere that the two separate brake contacts in the single brake switch must operate perfectly simultaneously.

So, when this deluge of rain from Florence is gone, I'll install a new brake switch and see what happens.
 

Seatman

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Joined
Apr 23, 2010
Location
Scotland
TDI
2014 Skoda rapid elegance 1.6 cr tdi
Not sure the clutch pedal switch would have any effect other than prevent the cruise from working?

The brake switch is usually two in one with only a single plunger, I've never come across any accelerator issues with a bad switch, just no brake lights or cruise.

Could it maybe be a bad earth?

I had the no pedal issue ages ago on the seat cordoba, ended up being water in the ecu but I could still drive everywhere at 30mph lol
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
So, when this deluge of rain from Florence is gone, I'll install a new brake switch and see what happens.
Makes sense

drag the brakes and the stock ECU shuts off power
there is a way to fix it in the binary, just search for "brake boosting" or something similar on ecuconnections
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, for what it is worth, on my very first road test (August, 2012), about 3 miles from my house the Accelerator pedal went dead and the idle defaulted to about 1100 RPMs. Too long ago to remember what the DTCs were.

Anyway, someone inquired if I had used lead solder on the wiring splices ... Yes! So, they said the ECU doesn't like the resistance changes.. So, I cut out those splices and did the twist with shrink tubing. As I demonstrated previously, everything is inside or protected from water. I really don't think water or dampness has anything to do with what's going on.

Seatman, I believe at this point, I need to install the new brake switch which I ordered and received several days ago. And, yes, I understand that the clutch switch shouldn't have any effects on the issues I'm experiencing.

Lastly, if the new brake switch doesn't eliminate the problem, I believe it will be time to dig into those splices and connectors .......
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Anyway, someone inquired if I had used lead solder on the wiring splices ... Yes! So, they said the ECU doesn't like the resistance changes.
no way
there's two pin terminal connections, the carbon track resistor with a spring finger on it, and at the very least two solder connections inside the ECU
all that on each wire

it does not care about good splices
maybe wire nuts getting splashed with salt water from time to time, but solder ain't no thing to electrons (and lead free solder is only for water pipes in my head)
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
I don't buy it either. The resistance of the solder between the wires is insignificant.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, all I can say, is that I cut-out every splice that was soldered together and no more dead pedal issues like I've recently experienced. That was August, 2012.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Okay ....... bringing this back to the top. (Although Scangauge is mentioned, I've been using VCDS also.)

Here's the deal: Seems the Accelerator pedal may be okay now "and" may not have totally been the problem. However, I did not re-install the one that supposedly went bad. (I'll do that tomorrow.)

Anyway, since August, 2012, from time-to-time there's been a an Implausible Signal relating to the Brake Switch. It's always gone away after a couple of restarts. Scan Gauge doesn't show that DTC for some reason. However, that DTC comes with the DTC for the Accelerator Pedal in combo with Flashing GP. So, when I scan with SG and deleted codes apparently the DTC for the Brake Switch is dumped too.

But, now, even with a brand new Brake Switch I cannot totally eliminate that Implausible Signal DTC. It may take two or three start-ups but the DTC for Implausible Signal from the Brake Switch will re-appear.

So, the Brake Switch is a double switch mechanism. Brake light part is normally Open and the Cruise Control part is normally closed. So, unless they are not closing and opening mighty darn close to the exact same time, the ECU is happy. Anyway, I know the old switch and the new switch are good... they are both exactly like the one Corey from Idparts shows how to install on a YouTube. I do know how to set the B switch when installing it. Adding a couple of layers of felt on the stop once set doesn't help with the issue at hand. Also, I did do several start-ups with pins 2 & 3 jumped on the brake switch. Those pins go to the normally closed switch. The ECU should have been happy with that but unfortunately, still got the same DTC.

So, this evening I did an Ohms check on all the circuits involved. I never found anything way off. In fact, all the circuits were about the same. I checked everything from the colored connectors back to the switches on both sides as well as the Clutch Switch for Cruise kick-out. However, from the colored connectors to the ECU, I did not do an Ohms test. But, other than re-bundling those wires for their new location they have remained intact and unmolested.

So, is it possible that the long distance from the Brake and Clutch Pedals in the Vanagon to under the rear seat possibly resulting in too much resistance? Keep in mind, the Brake Switch is just that, a switch with two leads that go all the way to the rear.

Lastly, not knowing the resistance limitations, I am stabbing in the dark.

Thoughts.
 
Last edited:

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
So, is it possible that the long distance from the Brake and Clutch Pedals in the Vanagon to under the rear seat possibly resulting in too much resistance? Keep in mind, the Brake Switch is just that, a switch with two leads that go all the way to the rear.

Lastly, not knowing the resistance limitations, I am stabbing in the dark.

Thoughts.
The brake light side of the circuit is heavier wire for the 3 lights involved.
I can't see a problem there unless there was loose connection in one of the plugs or a very corroded wire. I would expect to see dim brake lights for this.

The cruise side sounds like a low power signal so a bad connection or the corroded wire might be more of a problem.

I never worked on my brake light switch, VW replaced it under a recall.
Do you have an old relay you could use to insert one of the pins into the brake light switch plug (one hole at a time obviously) to see if it's a tight fit?
Judgement call of it. :)
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Yeah, Wonneber, in my case, the ECU only monitors one brake light bulb. Considering for testing purposes, I am starting the engine without pushing down the brake pedal the ECU sees nothing. However, to be sure, I may add another light bulb just for the tests. But, this one bulb set-up seems to have worked okay. The DTC I'm getting now just will not go away. That's why I think it is with the Cruise Control circuit side of the brake switch.

Okay, as stated, I did jump the contacts for pins 2 & 3 which are for the Cruise. The wire I used for jumping was a tight fit. With the brake switch (pins 1 4) normally open, the ECU should be fine with that when just starting the engine. So, jumping pins 2 & 3 did not make a difference.

So, today, I am going to jump those two circuits (from pins 2 & 3) right at the source under the back seat where the ECU is located.

I'll post the results.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Okay, from one of the branch circuits from Relay 109, power is provided to Fuse #43. On the down side (43a) power goes to a number of circuits, of which, one goes to the Cruise side of the Brake Switch (merely a switch). From there the current goes to the Black Connector at T10e/5 on to the ECU #65.

Quite simple-> 12 volts from Fuse #43 to ECU 65 with a switch in the middle that is normally closed... hint, touch the brake and the Cruise is kicked-out.

So, that's how I by-passed everything, 12 Volts to the T10e/5 circuit which goes directly to the ECU at #65.

NO CEL or Flashing GP with the By-pass after numerous shut-downs and re-starts (that's when the ECU monitors that circuit).

So, there is something going on in either the wire (and splices, two I think) to the Brake Switch or the wiring coming back (and splices, two I think) to T10e/5.

Thoughts? Would you start by eliminating the soldered splices?

Keep in mind, the wires (circuits) are all in cable bundles which are inside water proof conduit under the Van and come up under the back seat one end and up under the dash on the other end. Water contamination, in my opinion, is not the problem.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, checked volts at the Black Connector circuit, which starts from Fuse 43 goes to the front of the Van to and through the Brake Switch... 12.79 volts (engine shut-down). Voltage at all other circuits nearby were 12.82 volts. So, I'm convinced it's not a voltage loss due to resistance. Besides the splices (two, one up front and one in the rear on each wire [up and back]) and three connectors, one at the Brake switch, one before the Black Connector and the Black Connector itself, I'm thinking one or more of the connectors may have considerable resistance at times due to mild corrosion.

Clean connectors ... is in order. Simply unplugging and re-plugging doesn't always solve the problem.

Anymore thoughts/comments are welcome!
 

wonneber

Top Post Dawg
Joined
Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagon,2003 Jetta 261K Sold but not forgotten
Thoughts? Would you start by eliminating the soldered splices?

Keep in mind, the wires (circuits) are all in cable bundles which are inside water proof conduit under the Van and come up under the back seat one end and up under the dash on the other end. Water contamination, in my opinion, is not the problem.
If the joints were clean and shiny when you soldered them I would thing they are all right. I've never had a problem with my soldered connections.

One of the very few things I liked from Radio Shack was their solder.
You did use rosin core solder, not acid core?
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Well, after using some DeoxIT on the connectors involved, the problem seems to be solved. After driving it about 15 miles, several re-starts and doing some scans, no DTCs. I could not see any corrosion on any of the pins or receptacles.

Hopefully, the problem is solved.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Gees! I let the Van sit from Monday evening until about an hour ago thinking the issues were behind me.

So, now the idle is at 1281 RPMs.

Scan Gauge shows no codes.

VCDS shows no codes.

I plugged-in the old Accelerator Pedal and it is dead as I thought. Then, I plugged-in another Accelerator Pedal and got the 1281 RPMs. The two good pedals do respond to acceleration. I've started and re-started numerous times with no change.

Lastly, Monday of this week, I did get a P1246

-Fuel Supply interrupted/faulty (from Ross-Tech website)

  • Fuel Tank (temporary) empty
  • Fuel Filter blocked
  • Air in Fuel System
Wiring and/or Connector(s) from/to Needle Lift Sensor (G80) faulty
Needle Lift Sensor (G80) faulty
Injection Pump faulty
------------
Air in the system was probably the reason for the 1246 DTC. I had removed the fuel pipe from the filter to the IP. Engine did start and idled a bit rough for a few seconds. I've driven the Van since then and been through all the start-ups and that DTC has not come back.

Thoughts...
 
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