ECU Replacement Help

[dpatel710]

Hi All,

 

The P!G has had a rough few months. Yesterday, while driving home, it cut out at an intersection and would not turn over. I walked over to the parking lot it was in and did some troubleshooting today. 

 

The car will not turn over, displays "foot on the brake", and gave the psm error when it died. With vag-com, I am unable to communicate with the engine but am able to access other units. I checked the trans and the error it returned was no communication with the ecu. From here, I checked all the ecu/psm related fuses as well as the ecu under the hood. The unit itself was dry and the connections had no oxidation or rust, so I am guessing it fried on the inside. Also, with the ignition on, the radiator fans start running. 

When swapping out the ecu, is there anything particular I need to look out for? I have coding ability with vag-com but am unsure if there are any specific porsche only parameters which may need to be coded. 

 

TIA!

Edited October 14, 2017 by dpatel710

[JFP in PA]

1 hour ago, dpatel710 said:

Hi All,

 

The P!G has had a rough few months. Yesterday, while driving home, it cut out at an intersection and would not turn over. I walked over to the parking lot it was in and did some troubleshooting today. 

 

The car will not turn over, displays "foot on the brake", and gave the psm error when it died. With vag-com, I am unable to communicate with the engine but am able to access other units. I checked the trans and the error it returned was no communication with the ecu. From here, I checked all the ecu/psm related fuses as well as the ecu under the hood. The unit itself was dry and the connections had no oxidation or rust, so I am guessing it fried on the inside. Also, with the ignition on, the radiator fans start running. 

When swapping out the ecu, is there anything particular I need to look out for? I have coding ability with vag-com but am unsure if there are any specific porsche only parameters which may need to be coded. 

 

TIA!

 

You cannot just swap DME's as the Vag-com will not be able to do all the necessary recoding; that requires access to a PIWIS

[Loren]

You would also need IPAS codes for your car;s DME as well as IPAS codes for the donor car.

[dpatel710]

Thank you for the replies. 

Would this be something the dealership can do? Or a tuning company? 

I live in a rural area so I would like to be able to take the ecu's somewhere rather than tow the suv. 

[JFP in PA]

They are going to have to have a PIWIS, which all dealers do, as well as some independents.  You need to ask if they have one as you are going nowhere without it, and for security reasons, they are going to need the car as well..

[dpatel710]

Would it be possible to post the pinout for the ecu connectors? I would like to check for power to the ecu to rule out wiring problems. 

 

I'm not much for electrical diagnosis but using the material I have, it looks like I should check pins A3, 21, and 23 for possible power? 

171016130452.pdf

Edited October 16, 2017 by dpatel710

[JFP in PA]

Unfortunately, that diagram is copyrighted material, so posting it would be a violation of intellectual property rights, which is prohibited on this site.