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Discussion Starter #1
I have a beautiful 2002 GLX 4 Motion v6 Passat and it is my baby - we have been through thick and thin, but this has me completely stumped. I fixed a major exhaust leak and I was testing it out and having a bit too much fun going around 100 mph when the engine completely died and I had no power steering, no power to the fuel, nothing. The battery is fine, the radio and dash lights fire up when I put the key in, but when I crank it, it turns over and over and the gas doesn't hit.

After inspection, I noticed a major vacuum leak. The tube completely broke when I touched it because it was so brittle. It's the bottom-right tube on the diagram under the hood, going to the vacuum reservoir, but I'm not sure if this could cause a crank, no-start condition like this. I plan on fixing it soon, but my pain priority is getting the car to start and/or the fuel pump to fire.

I have a diagnostic tool and it is unable to read any codes at all. When I turn the car on, all lights turn on except for the check engine light.

The fuel pump was replaced within the last 2 years, but it was a cheap one from eBay. I have a new one that I plan on trying tomorrow along with a new fuel filter, but this seems like an electrical issue to me (I am a relative novice and practically everything I know has been from working on this car and minor issues on others). If it was an issue with the fuel pump alone, I feel like I would at least get some codes from the diagnostic tool.

I have visually inspected all the fuses in the box to the left of the wheel, and all of them seem fine. I tried swapping the ABS fuse #7 and also fuse #15 as mentioned in another post here to no avail. All fuses seem fine to me.

It's hard to get the cover of the ECM off under the hood, so I don't want to do this if I don't have to. Are there any other simple fixes that could potentially solve the problem, or would my next step be to check the voltage of all the wires going to the ECM?

Any and all help would be greatly appreciated. I'm moving soon and I need this fixed ASAP, but I have all of 4th of July weekend to work on it.

Thank you guys so much
 

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Do you have an aftermarket radio? If not, try to unplug the ABS connector and see if the car can be scanned. The vacuum line would make starting more difficult, but usually it would start. Is the timing belt in good shape?
 
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When you say "I have a diagnostic tool and it is unable to read any codes at all"
Do you mean that you get an error, or that there are no codes to read ?

Does the tacho needle move while cranking ?
Measure the voltage at fuse #28 (with fuse connected) while cranking, is it above 9V ?
 

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Discussion Starter #4 (Edited)
I have a cheap diagnostic tool and (unlike before) it takes forever to scan, but eventually it states that it is unable to scan any codes (error). Before, it would have a ton of codes. The check engine light will not come on.

I had a buddy help me take a look at it and there is no spark to the spark plugs or the coils. I already changed the coilpack to no avail (I also fixed the vacuum leak). The electric connector to the coil pack is a bit screwed up because of having to take it off to get underneath it for other fixes, but all connections still seem fine visually to me.

Tomorrow I have a crankshaft position sensor coming in that I will try. If it's not that, I suspect a short somewhere.

I do have an aftermarket radio, but I can still try disconnecting the ABS connector if you think that could be an issue.

Could a bad timing belt cause a no spark? it Its very possible that my timing belt slipped and I planned on changing it soon anyway, but I want to know if that could be why it wouldn't spark.

No needles move while cranking, and check engine light does not turn on. I'll try to check the voltage at fuse 28 tomorrow.

Thank you guys
 

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to get to the ECM (remove cover) if you ever need to, there is a small ,quarter sized snap in access plug/cover by the drivers side wiper arm that you remove allowing you to get to the "last" screw in the back of the cover.
 

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Is fuse #28 good, and what is the voltage while cranking ?
As you damaged the coil connector, I strongly recommend that you don''t go near the ECU, and the fault is unlikely to be there.
I suggest you completely disconnect the radio including any adaptors, then try a scan.
(leave it disconnected until you get everything else working)
If you still can't scan, try with the ABS unplugged.
 

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Discussion Starter #7
Man I got off work, got a new crank sensor, I was in the process of changing it when it started to downpour. I'd kill for a carport right now. If that doesn't work, I'll try all your suggestions and keep you posted with the results. Thanks again
 

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Discussion Starter #8
Is fuse #28 good, and what is the voltage while cranking ?
As you damaged the coil connector, I strongly recommend that you don''t go near the ECU, and the fault is unlikely to be there.
I suggest you completely disconnect the radio including any adaptors, then try a scan.
(leave it disconnected until you get everything else working)
If you still can't scan, try with the ABS unplugged.
Ok, so far I have replaced the coil pack and crankshaft position sensor. Fuse #28 reads at 0 ohms, so I'm pretty sure that means the fuse itself is good. There is no voltage (I tried both AC and DC) while cranking. I have disconnected the radio completely. The OBD tool stops loading halfway. Battery light is always on, check engine light is never on.

Something I'm not sure is related-when I try to adjust the seats, I hear a couple clicks and they won't move.

When you say to unplug ABS, do you mean the two sensors behind the front wheels? So I would need to disconnect from both sides? Or are you referring to something different?

Thanks for your help.
 

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To disconnect the ABS means to disconnect the controller that is under the hood. If it fails it can flood the CAN bus with garbage messages and cause all sort of havoc. The brakes will still without it but there will be no ABS functionality.
 

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A note on the ABS controller: it uses a very large connector with a slide latch. As you pull on the slide latch the connector gradually "unplugs," evenly across its whole width. It might need a little help, but know that it's very different from most smaller connectors, where you just release the latch then tug.
 

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Discussion Starter #11
Thank you guys. I have done everything you have said to no avail. I thought a video may display my situation a bit better. Any and all help would be appreciated. Last resort is gonna be getting it towed to a mechanic, but I really don't wanna have to go there. Thanks again for all your help, please watch this quick video

 

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If there is a wiring adaptor for the radio, that also must be disconnected.
Don't replace parts unless there is an indication they are faulty.
What was done or happened, between the last time the scanner worked and the first time it didn't work ?
 

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Discussion Starter #13
I believe I disconnected it to no avail. I'm thinking there's definitely a problem with communication to the ECU, but I don't know where to begin. Does anyone know how or what to test for when looking at power from the ECU to the coil pack? Just want to make sure that isn't the issue. I removed the orange part for better visibility.

All I have done since the code reader wouldn't work was fix a major exhaust leak and drive near 100 mph. It was soon after that when everything stalled.

Wiring adaptor for radio?
100062


Still won't read.
100063


ECU/ECM to Coil pack connector - could this be where the problem is? How can I tell with a voltmeter?
100064


Thank you!
 

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Have you tried the scanner on another car just to make certain the scanner is not the problem?
 
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Discussion Starter #15 (Edited)
No I have not, but I can try that tomorrow. But the fact that the ECM isn't even communicating to produce a check engine light says something to me. I had one more really experienced guy double check everything I have witnessed and done, and he concluded it must be a problem with the ECM itself.

When I cranked, we noticed a distinct burnt electronics smell coming from the ECM or ECU and he swears that must be the problem. I took the leap of faith and ordered a new one for $50 on eBay and it will get here Tuesday. I am planning on taking the unit apart tomorrow to see if I can notice anything abnormal, as it was getting dark at the time and stuff was hard to see/maneuver (wish I didn't have to work all day). I also tried looking for an ECM relay, but from what I understand, the v6 does not have one. I only see a 373 relay which seems to have nothing to do with it. Can anyone confirm?
 

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I have a beautiful 2002 GLX 4 Motion v6 Passat and it is my baby - we have been through thick and thin, but this has me completely stumped. I fixed a major exhaust leak and I was testing it out and having a bit too much fun going around 100 mph when the engine completely died and I had no power steering, no power to the fuel, nothing. The battery is fine, the radio and dash lights fire up when I put the key in, but when I crank it, it turns over and over and the gas doesn't hit.

After inspection, I noticed a major vacuum leak. The tube completely broke when I touched it because it was so brittle. It's the bottom-right tube on the diagram under the hood, going to the vacuum reservoir, but I'm not sure if this could cause a crank, no-start condition like this. I plan on fixing it soon, but my pain priority is getting the car to start and/or the fuel pump to fire.

I have a diagnostic tool and it is unable to read any codes at all. When I turn the car on, all lights turn on except for the check engine light.

The fuel pump was replaced within the last 2 years, but it was a cheap one from eBay. I have a new one that I plan on trying tomorrow along with a new fuel filter, but this seems like an electrical issue to me (I am a relative novice and practically everything I know has been from working on this car and minor issues on others). If it was an issue with the fuel pump alone, I feel like I would at least get some codes from the diagnostic tool.

I have visually inspected all the fuses in the box to the left of the wheel, and all of them seem fine. I tried swapping the ABS fuse #7 and also fuse #15 as mentioned in another post here to no avail. All fuses seem fine to me.

It's hard to get the cover of the ECM off under the hood, so I don't want to do this if I don't have to. Are there any other simple fixes that could potentially solve the problem, or would my next step be to check the voltage of all the wires going to the ECM?

Any and all help would be greatly appreciated. I'm moving soon and I need this fixed ASAP, but I have all of 4th of July weekend to work on it.

Thank you guys so much
Try changing the ecu relay had same problem with my 2001 passat ended up putting alot of money into it and my relay was like 40 bucks and that was the problem
 

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Discussion Starter #17
Try changing the email relay had same problem with my 2001 passat ended up putting alot of money into it and my relay was like 40 bucks and that was the problem
Hello 01turbo, thank you for the suggestion. Where exactly is the email relay and where is it located? Is there another name for it?
 

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Wiring adaptor for radio?

ECU/ECM to Coil pack connector - could this be where the problem is? How can I tell with a voltmeter?
Sometimes there is an adaptor between the radio and the car wiring,
you might need to pull the wires out of the dash a bit to find the connectors.

No, the coil pack or its connector are NOT the problem.

How to check the K-Line:

With radio and adapter kit un-installed:
Step 1:
You'll need a 1k Ohm (approximately) resistor. Put it between pins 4 and 7 of the
diagnostic connector. Switch Ign. on and use a volt-meter to measure the voltage
between 4 and 7 (in parallel with the resistor).
If it's under 1V, you don't have a short to + 12V.
If it remains near 12V (the resistor will get hot!) you do have a short to + 12V. Remove resistor.

Step 2:
Switch Ign. off and disconnect the battery.
Measure resistance between pins 4 and 7 of the diagnostic connector.
If it is very low you have a short to ground.
If it is very high you have a break or bad connection in the K-Line.

If you have a fault in the K-Line.
You can do the following checks one at a time in any order.
You will need to disconnect modules one at a time (I would start with the CCM) and
check for shorts and bad connections in the wiring, until the K-Line comes good.

____

If any part of the K-Line is shorted to + or -, it kills the whole line, and prevents scanning.
The K-Line connects to the modules inc. Original radio and the OBDII port.
Ross-Tech: VCDS: Afterrmarket Radio Problem
You can use the test near the bottom of the page to check the K-Line, and find what type of fault exists.
 

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All I have done since the code reader wouldn't work was fix a major exhaust leak and drive near 100 mph. It was soon after that when everything stalled.
That doesn't answer my question.
"What was done or happened, between the last time the scanner worked, and the first time it didn't work ?"
 

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Discussion Starter #20
That doesn't answer my question.
"What was done or happened, between the last time the scanner worked, and the first time it didn't work ?"
Well, to my best recollection, it was working before that incident. The only thing I replaced was the crankcase vent valve because the other one blew.

I have done my best to follow along with your other suggestions and I will continue to work on the steps you have provided, but the fuel pump relay was definitely acting funny so I replaced that.

I opened up the ECM and this is what I found.
100114
 
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