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I think I screwed up

1085 Views 5 Replies 2 Participants Last post by  ______TJ______
was at a friends trying to get vagcom to work, I have a problem with my K line and it will not let vagcom communicate the any module. I started pulling fuses and relay hoping that the vagcom led will change color. someone from ross tech told me that a red led on vagcom cable means something is wrong with the K line and vagcom won't work.

anyway, I had the ignition on for a while and now my car doesn't run. it tried to start, I smell fuel. It just seems like it isn't getting a spark. Are ignition modules known to go bad?
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Damn I was checkin' in to see how you were making out, and I found this post..

Before you do anything, I am not trying to be funny, but when shit gets hectic, we forget things...Check every fuse again with the meter..twice :)
Also make sure every relay at the bulkhead is seated and plugged in all the luck?.... read on...

ICMs are a common problem... you need to check the pins of it on top of the airbox with a meter, not sure of the values...hold on I will go get the Bentley..I keep in the trunk :) Hint :).......................................................................................................................................................(digging in trunk, spare parts..oil...hmm) Got it!!


First be careful when testing the pins, no biggie, just be clean
If you fry something else, it's on you... no real worries..just a disclaimer :)

Top of the air box there are two plugs that plug into the oval seated module, the first test involves the larger of the two plugs;

Disconnect all plugs from the injectors...

Pin 3 is ground
Pins 1, 2, 4, 5 are cylinder activation outputs, the factory test involves a led, but I am pretty sure you can test it with a multimeter set to the mv scale.

Example: Pin 3 to ground lead on the meter: pin 1 to positive
then subsitute 2, 4, 5 using pin 3 as ground.

Crank the car and make sure there is activity on all of the activation outputs..

If not reconnect the 5 pin harness, and disconnect the 4 pin connector then use the ground from the multimeter to pin one and the other to battery positive, operate starter to check the output stage of the icm, repeat this test for pins 2, 3, 4 Use the 12v standard scale for this test.

I substituted the meter for the VAG 1527 b tool, which is just a voltage safe "Test Light" that draws no current. You can do the same, or if you are sure you have a led based "air Bag" safe test light you can use that.

So it would seem from this: the 5 pin side is ECU level control voltage and the ICM steps it up into a stronger negative output to fire the coils thru the 4 pin..

Hope that helps, maybe that was your original code, and the long term "on" but no start pushed it over the edge? The thing does have a heatsink inside the air box so I am sure it gets hot.

Here is a thought, why don't you stick your ECU in a friends car just to read the codes? if you have a similar car, year and such?

Even if it is 5 speed, it may help you figure out where the car was headed?

As far as the K line is concered, I would pull the radio and disconnect the plugs from the back of it, making sure all the pins are good and no shorts.

Keep it completely disconnected and, try to scan again..

the other consideration is where else the k line "goes"...this means check the CC module under the rug drivers floor, take it out check the pins, wires...etc.
Then remove the TCM and do the same, in the passenger floor, under the carpet...

Good luck ..

let me know...

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Thanks, I got a Bentley also. I would keep it in the trunk, but it may not retain its disc shape :)

Just after I posted this thread I found all that info in my Bentley and performed all of the checks. Everything checks out with the ICM, RPM sensor and camshaft poistion sensor. I also went back over everything under the dash and everything is exactly how it should be. After I rechecked that I called the dealer. My car is there now. I didn't want to jack with it and since it isn't mechanical I don't mind someone else fixing it. Plus I got my extended warranty to pick up the tab.

I talked to the tech after he spent about 5 minutes with my car. He was able to get teh ECU to pull then engine DTC's, there were 13. One was dealing with the fuel pump relay which is exactly what I was checking at my friends house, then he lost connection. My car has a K line problem. He will have to find out what controller/module is tying it up and then he will be able to scan for codes. I should hear from him tomorrow and I will post it up.

Damn I need a VagCom! :(
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I keep the book in the car, and the disc in the drive ;)

I find the disc is good for research, but the book is infinitely better for hands-on working on the car, no scrolling...easy to jump sections..


Keep us posted, I want to the the code list, very interested.

glad it will be up and running again...for free no less!!

Good Luck Jem,

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Well they had my car for a while, but I got her back today. I still have to take her back for a day when they get the new crash sensors.

One of the problems was the Airbag module. They ordered a new module but when it got here they thought it was the wrong one. Turns out the part was replace, superceeded by this new module that uses a different crash sensor. So I have an airbag light on and my airbags don't work until the new sensors are installed on tuesday.

The other problems was the instrument cluster module. It was replaced and all is good now. I asked about knocking off a few thousand miles, but that didn't go over well :oops:

I'm not sure what was wrong with either module but both would prevent communications with any module. When you unplug the two modules communication was restored.

The only thing that feels different is the way it shifts gears. Everything seems to happen all at the right time. Before it felt like things were out of time and shifts were usually less then smooth. Also my tranny used to engage drive and reverse pretty harsh, now that the modules have been replace it is 90% better.

Tomorrow I am going back over to my friends house and we are going to recode my tranny to 00010. What did you want me to log for you TJ? I know you wanted to know my fuel trims, but I thought you wanted something logged?
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Well Jem,

If they cleared all the codes, they also cleared the fuel trim data.

It would be nice to see where your trims sit after 3-4 days of driving.
Block 032

I would also like to see a list of codes from the incident.

A 4th gear pull starting at 2k or so to redline pull of :

02 voltages (either 030 or 031) I forget now.

Block 002 would be nice or anything with g/s at the Maf and timing

And finally, timing correction, I think that is in the "teens" as far as blocks go..? I usually just advance thru them until I find it.

make sure to log one at a time for resolution and sample rate, the newest version of the Vag has an adjustable sample rate, so crank that up!!

I am happy for you the car is back, I know that sucks..

Look forward to seeing some data to compare..

Congrats, :D

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