How I fixed fault code 17911

About a month ago I was leaving the in-law's place and the Jetta's check engine light came on and stayed on - meaning I had an engine issue. I nervously drove for 3 days trying to see if I could hear anything abnormal coming from under the hood before I could get a hold of a VAGCOM (thank you Tom!) to pull my fault codes. When I finally plugged it in it displayed two codes:

17058 - Cylinder 4 Glow Plug Circuit (Q13):
Electrical Fault
P0674 - 35 - 20 - - - Intermittent

17911 - Load Signal From Alternator Term. DF:
Implausible Signal
P1503 - 35 - 10 - - - Intermittent

Having read Wingnut's Glow Plugs 101, I knew how to proceed with the glow plug fault but was stumped as to what the second code meant. So being a good little TDIclub member I did a thorough search and came up with little on how to fix the code. I do have to give credit to Whitedog for finding information on the fault on a Seat site and posting it up here. Since we don't already have anything on the topic, I figured I would get this out there. The code, by the way, does not display a CEL (in my case the glow plug fault did that) but gets stored nonetheless. My car seemed to store the code everyday - I cleared the code at night, commuted the next day and checked the codes when I got home with it displaying the 17911. I repeated this 3 times, all having the same results.

The problem: On the front side of the engine is a harness that runs from the alternator, voltage regulator, and A/C compressor (if so equipped) to the main harness underneath the battery box. Apparently, VW decided to make this harness ~1" shorter than it should be which becomes an issue at a four pin connector (2 pin in the case of no A/C) located on the starter.

There are five wires in the harness:
1) Large red power wire from the alternator. Goes to the fuse panel on the top of the battery.
2) Green and black wire from A/C compressor (actually for A/C compressor clutch). Goes through third pin on the 4 pin connector to ?
3) Brown and black wire from A/C compressor (actually for A/C compressor clutch). Goes through fourth pin on the 4 pin connector to ?
4) VERY small brown and red wire from the voltage regulator. Goes through the first pin on the 4 pin connector on its way to the ECM.
5) VERY small blue wire from the voltage regulator. Goes through the second pin on the 4 pin connector on its way to the ECM and Generator indicator light in the dash, as well as the warning chime.

On my car, #4 was completely disconnected; #5, and #3 were also well on their way (the sheathing had cracked and the wires were frayed).

My first step was to pull the harness from the car to see if I could salvage the connector. To do this the battery, battery box, air cleaner and engine cover came out to gain access to the various points of attachment. Once out, I noticed that all the damage to the wires was less than 1/4" from the connector making soldering somewhat difficult. I came up with 2 ways to fix the short, broken harness: 1) pull connector apart, lengthen wires, rebuild connector 2) remove connector, lengthen wires, permanently attach the harness. I decided to go with the latter option since I kinda mangled the connector trying to pull it apart (I don't think they are meant to be serviced) and also because I didn't think the connector was necessary.

So out came the soldering iron, wire strippers, heat shrink, 16ga wire, and wire loom. The whole process was pretty painless, that is if you don't count the couple of times I burned myself and the 10deg parking lot that I had to do the fix in . I buttoned everything back up and fired it up and took it for a spin, keeping my eye on the CEL to see if anything had been screwed up - nothing. When I got back I ran a VAGCOM to see if the 17911 was stored again and....success, no more implausible signal.

I look forward to see if this fixes my other problem of frequently blowing taillights, headlights and brake lights. My guess is that the completely disconnected wire was touching one of the other exposed wires in the connector...possibly the ground (?) for the A/C.

Anyway, I hope this helps shed some light on the 17911 fault code. Happy TDI'ing.

Good fix. Have to keep this one in the memory banks.

I know at least one other TDI Jetta (2001) driver that has gremlins blowing lights alot. Definitely interested to hear if that problem clears up.

Figured I should complement this thread with some pictures of what I'm talking about. Here is the plug (removed from the car of course):



The damage to the wires in locations 2 & 3 is obvious but what is strange to me is the clean cut of wire one as if it had been cut on purpose. Maybe this is a ploy by the dealership to get make some money.

Imagine this: customer comes in and says they are blowing bulbs and their MIL is on. Service guys says "Yup, looks like you need a new alternator," even if you knew something about cars this seems like a reasonable diagnosis. They throw in a new alt (keep the good used one) fix the wire and charge the customer $600 for being a sucker.

Anyway, here is the location of the connector below the battery box directly on top of the starter:



Another view:



Finished product:



NO connector, no blown taillights, brakelights, headlights, and no more 17911 code (just checked the fault codes tonight).

Great fix. I'm glad I could help even if I don't have a clue what I did.

Here ya go: http://forums.tdiclub.com/showthread.php?t=145253 post #4

Isn't search grand?

Hmmm I almost remember posting that.

Thanks for this thread.

I have the same code being thrown and just checked the connector. One of the wires is completely severed.

I was hoping sooner or later this was going to help someone.

I pulled out my battery this passed Saturday and fixed it using some old 16ga speaker wire. The severed wire was about three inches away from the connector so I left it intact and just replaced the affected wire.

I cleared the codes using VAG-COM and so far so good!

Thanks again!

Maybe that mysterious red hand under the hood tampered with the wires.

Didn't see a red hand in my engine bay. Wish I had one though.. it would catch some of the bolts and sockets that I've dropped down there over the years.

Oops.

::::::

Okay, I'm only four years late!



Thank you soooo much for posting up this solution! <bows down>

I recently bought a Skoda Octavia with a whole raft of annoying electrical faults and non-working a/c.......and this one job fixed them ALL!

I did it the hard way though; fitting a new connector. Call me old-fashioned (stop shouting at the back LOL!) but when have you ever known VW fit a connector it could save a buck on by not fitting? Suggests to me there has to be a reason, I guess to make engine/tranny removal easier?

Anyway, I'm stray from the point, I am delighted that someone took time to post up this solution, indebted to you guys!

Thanks,

Bro

This is why I like to stay subscribed to threads. Sometimes they bring back memories of stuff to look for. I had completely forgotten about this and forgotten that I had forgotten that I had forgotten about finding what others did to fix it.

BTW, the original post was 7 years ago.

whitedog said:

This is why I like to stay subscribed to threads. Sometimes they bring back memories of stuff to look for. I had completely forgotten about this and forgotten that I had forgotten that I had forgotten about finding what others did to fix it.

BTW, the original post was 7 years ago.

Click to expand...

Yep, but at least the guy did some searching to resolve his problem.
Nice work!
And great job by Nick for the fix "how to", too, also, etc....

brother52 said:

Thank you soooo much for posting up this solution! <bows down>

I recently bought a Skoda Octavia with a whole raft of annoying electrical faults and non-working a/c.......and this one job fixed them ALL!

I did it the hard way though; fitting a new connector. Call me old-fashioned (stop shouting at the back LOL!) but when have you ever known VW fit a connector it could save a buck on by not fitting? Suggests to me there has to be a reason, I guess to make engine/tranny removal easier?

Anyway, I'm stray from the point, I am delighted that someone took time to post up this solution, indebted to you guys!

Thanks,

Bro

Click to expand...

Fantastic! I'm glad to see this is still helping others and kudos to you for searching. If I were to do this repair today I would also try and source a new connnector and splice into the harness. Having said that I've had my transmission out twice among other service in the area and have never regretted eliminating the connector.

I think this is what is happening to me as well. Thank you for the post and I will hopefully find some broken wires.

Have you still been blowing lights?

Nope.

So maybe the under/over voltage was blowing the lights afterall. Intervesting.

I still never remember this thread until I get pulled over and finally decide to search to find what's going on. I wonder what the poleecman would say if I started searching while he was telling me that my tail light is blown out again.

Less than two weeks and another blown bulb. I really need to check into this.

Edit: I just looked at my harness and it looks perfect. SIGH...

I would check for a bad ground.
Measure the voltage from the battery negative post to the bulb brass case while the light is lite.
You could do the same on the positive side but you would need to poke into the wire at the bulb.

In vcds, when you go to controller 1 (engine) and from measurement blocks check 53. Do you see the alternator load (4th field) changes based on if you have all electrical things inside car on/off?


I have a problem that the value stays fixed all the time whatever I do inside the car.

I've been having issues with a dead battery I thought were caused by parasitic drain from a cheap bluetooth audio adapter that plugs into the cigarette lighter outlet. It's happened a few times, but this time it wouldn't take a charge so I bought a new battery. Battery came with the car, so it was at least 4-5 years old. For unrelated reasons, I also bought the bluelight wireless obd-II reader and just discovered fault 17911/P1503... this made me think that maybe it was my alternator that killed my battery. I didn't suspect the alternator initially because the battery was only ever dead after sitting. I took a little trip to autozone and had them do their thing-- voltage reg and alternator checked out fine.

Searched 17911, found this thread, checked the plug and sure enough found the brown wire-- #1 as marked on the plug-- severed at a crimp connector from a previous repair. I soldered in a new section of wire and thought my day was done. Not so fast... 17911 is back.

For all I know this wire has been broken since I got the car. I haven't messed around in that area since two winters ago when I installed a frost heater. What does this wire do? Any ideas about where to look next? Coincidentally, I also have a glow plug code-- cylinder 2 17056-- which I have not fixed yet. Is it possible that 17199 is simply related to glow plug circuit fault and doesn't have anything to do with this four wire plug? I'll replace the glowplug tomorrow and report back.

2 of mine are broken i assume they are the ac wires. Will investigate as i seem to have some draw or ground issue as the serp belt chirps with fan on high at idle. Even with new parts there ive put up with it for a few years kinda like a mole

Swapped the glowplug, which of course cleared that code. 17911 started being reported as "sporadic" and is now gone. Not sure whether repairing the wire or swapping the glowplug fixed it.

This was exactly the problem I just had. The red wire was broken. Now I can't solder to save my life but my son can! So I just cleared all the crap out of the way and told him to direct connect the wires through, heat shrink them, and we'll cover them with some split poly. All working normally again.

Thank you for this fix!