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Electrical gremlins - transmission coolant valve => water & shorts at Engine Computer
I'm new to posting, mostly lurk and look. In this case I didn't find many posts until I figured out my problem, then discovered that the A6 guys have been dealing with a version of this problem for years.
Even so, I figured I would post this on A4 though it was a problem on my 2013 A5 because I searched both forums and didn't see this fun problem.
The issue my car had was electrical issues that created codes that were not related to the root cause of the problem.
My car had intermittent rough running and loss of power as I was driving - not fun if you're expecting to accelerate and the car suddenly doesn't.
After the car started doing it more often I looked up the trouble codes and they lead me to look for shorts in the engine wire harness. When I pulled the main connectors off of the engine computer I discovered a bit of water at the connector.
See my picture of the computer as it was when I pulled it from the car.
I cleaned things up and got it to work but was totally at a loss as to how water could get into the connector.
When I looked closely at the connector it seemed like pin 35 was more corroded compared to the others so I figured that I needed to track down that circuit.
I was fortunate that a technician and SA at Prestige Audi Denver took some time to help me with my DIY and looked up the circuit and told me it was for the transmission coolant valve.
I was a bit surprised because my car has a proper manual transmission and I didn't think it would have water cooling to the 6MT but the technician showed me the valve and the messed up connection at that end.
See the picture of the two pin connector that plugs into transmission valve.
The coolant valve has a leak and water uses the wire insulation as a capillary tube to transport water from the valve connector to the ECM connector where it gets to short out other engine control devices like the coils.
Apparently this isn't all that uncommon, given that the Audi technician has seen it on various models.
There has already been a recall for A8 2010-2013
Also Audi has a TSB on it 10058574 8951
If anyone else has this issue and you think that power loss and potential stalling would be a safety problem please submit a complaint to nhtsa. gov
I think it would be important to mention how it was a safety issue for you. For me the sudden lack of power was an issue.
If it isn't a safety issue then it is just a failure you might get to deal with some day down the road.
Just had this happen. My mechanic told me that I had fault codes for both my ignition coils and the transmission coolant valve. Turns out the coolant leaked into the ECU connector and thankfully did not short the ECU. Lost the engine power and limped my way home.
Did you change out the valve and was that the end to the problem?
I have 6mt A4 and have a soft code for trans coolant valve open circuit
Originally Posted by JRB_brownA5
I'm new to posting, mostly lurk and look. In this case I didn't find many posts until I figured out my problem, then discovered that the A6 guys have been dealing with a version of this problem for years.
Even so, I figured I would post this on A4 though it was a problem on my 2013 A5 because I searched both forums and didn't see this fun problem.
The issue my car had was electrical issues that created codes that were not related to the root cause of the problem.
My car had intermittent rough running and loss of power as I was driving - not fun if you're expecting to accelerate and the car suddenly doesn't.
After the car started doing it more often I looked up the trouble codes and they lead me to look for shorts in the engine wire harness. When I pulled the main connectors off of the engine computer I discovered a bit of water at the connector.
See my picture of the computer as it was when I pulled it from the car.
I cleaned things up and got it to work but was totally at a loss as to how water could get into the connector.
When I looked closely at the connector it seemed like pin 35 was more corroded compared to the others so I figured that I needed to track down that circuit.
I was fortunate that a technician and SA at Prestige Audi Denver took some time to help me with my DIY and looked up the circuit and told me it was for the transmission coolant valve.
I was a bit surprised because my car has a proper manual transmission and I didn't think it would have water cooling to the 6MT but the technician showed me the valve and the messed up connection at that end.
See the picture of the two pin connector that plugs into transmission valve.
The coolant valve has a leak and water uses the wire insulation as a capillary tube to transport water from the valve connector to the ECM connector where it gets to short out other engine control devices like the coils.
Apparently this isn't all that uncommon, given that the Audi technician has seen it on various models.
There has already been a recall for A8 2010-2013
Also Audi has a TSB on it 10058574 8951
If anyone else has this issue and you think that power loss and potential stalling would be a safety problem please submit a complaint to nhtsa. gov
I think it would be important to mention how it was a safety issue for you. For me the sudden lack of power was an issue.
If it isn't a safety issue then it is just a failure you might get to deal with some day down the road.
Where is that connector located? I haven't dug into anything yet, I just had a recall done for the coolant after run. I don't have any other codes just the transmission coolant valve (P19A200) but doesn't trigger the check engine light.
The N488 transmission coolant valve (only for manual transmissions with gear oil heat exchanger) is likely right around the bell housing, probably not far from the V51 afterrun coolant pump which is on the bottom back left of the engine. Look for the two hoses that come out of the transmission and follow the one that goes to the valve.
Thank you very much! I really appreciate your time.
I've only had the car for just about 2 weeks, thus is my first Audi coming from VW I know my way around the car..
I just had the after run pump replaced due to recall, but the P19A200 keeps coming up, and I just couldn't make sense of it. I haven't had any driving issues and doesn't show a CEL.
again thank you very much for taking time to explain with pictures.
Cluster panel malfunction after ecm replacement from coolant leak
What's good ya'll. I have a 2013 a4 manual Trans and I had the coolant leak into my ecm and fry it. I replaced the ecm, cleaned up the engine harness connectors, and replaced the transmission coolant valve. When I plugged my ecm,(now under warranty)...I'm having the same issues after fixing the problem. Seeing my cluster panel still malfunctioning, rpm and mph gauges tick at the notch when the ignition turns on and my mmi turns on but after a few moments the mmi foes dark and my gauges just tick away like a clock arm. We tested every relay we could find and checked all the fuses to make sure everything was good. They are. See we sent my cluster panel in to be tested and fixed. The attachment is the email I received from the company after they said they could fix and replace my cluster panel... They said when they reansfered my mileage to the new cluster, the new cluster was doing essentially the same thing mine was doing
Were going to try another place and see what they say. Has anyone here had this problem?
05-29-2019, 02:36 PM
Electrical gremlins - transmission coolant valve => water & shorts at Engine Computer
