Still having transmission issues..

[zakx]

Hello, I have an '02 3.0 with the 5 speed automatic tiptronic in it. The 5hp19 transmission. I've had the car for over a year now. I was getting the p0751 code. I replaced the neutral safety switch, didn't fix it, replaced the oil and filter with genuine Audi oil and filter, didn't fix it, was also getting a code for tiptronic switch which was outting it in safe mode so I changed that as well, didn't fix it. Finally I was able to hook it up to a vagcom and it said shift solenoid A stuck on short to ground mechanical damage. So i bought a whole used valve body from a perfect driving car with solenoids and everything. Still same thing. the transmission just goes into safe mode. I hooked up vagcom and did a test for the voltage and I noticed that the volts greatly decreased as soon as the car went into limp/safe mode. Could this be something electrical? The dash also keeps telling me that all my turn signals don't work even tho they do.. Can something electric in the car other than the transmission interfere with the transmission? Also thinking maybe the engine speed sensor or the transmission speed sensor? Maybe tcu/harness? I'm tired of throwing money at it and just having it sit around collecting dust.. Any help would be greatly appreciated.

Also thanks to the diagnosticator for helping me out a lot last year

[zakx]

VAG-COM Version: Release 409.1-US

Control Module Part Number: 8E0 927 156 J
Component and/or Version: AG5 01V 3.0l5V USA 0808
Software Coding: 0001002
Work Shop Code: WSC 63351
1 Fault Found:
17135 - Shift Solenoid 1 (N88): Open or Short to Ground
P0751 - 003 - Mechanical Failure - Intermittent

[diagnosticator]

VAG-COM Version: Release 409.1-US

Control Module Part Number: 8E0 927 156 J
Component and/or Version: AG5 01V 3.0l5V USA 0808
Software Coding: 0001002
Work Shop Code: WSC 63351
1 Fault Found:
17135 - Shift Solenoid 1 (N88): Open or Short to Ground
P0751 - 003 - Mechanical Failure - Intermittent

The 17135 DTC indicates that the wiring harness internal to the transmission case is faulty. Specifically the wiring to the shift solenoid 1, N88. I recommend replacing the transmission wiring harness inside the transmission.

[zakx]

The 17135 DTC indicates that the wiring harness internal to the transmission case is faulty. Specifically the wiring to the shift solenoid 1, N88. I recommend replacing the transmission wiring harness inside the transmission.

I believe that was replaced too with the valve body

[diagnosticator]

I believe that was replaced too with the valve body

There is a fault somewhere. The wiring needs to be tested for the fault ID'd by the DTC. If the fault is not in the trans wiring harness, it is between the transmission harness and the TCU. Why do you believe the trans wiring harness was replaced with the VB? Are you sure? Since you have replaced the VB and trans harness?, the only possible cause remaining is the wiring between the trans harness and the TCU. If the fault can't be located, new wires from the TCU to the trans harness need to be run on the outside of the main wiring harness to bypass the faulty wiring to Solenoid A. "Shift Solenoid A Performance or Stuck Off" As in Stuck off, Not receiving any control voltage from the TCU.

The wire for the control voltage to solenoid A, N88 is from TCU pin 30 to trans harness connector T16g/8 (harness connector T16g, Black 16 pin connector, pin #8, at trans case.) 0.5mm diameter Green/Brown wire color.

[zakx]

There is a fault somewhere. The wiring needs to be tested for the fault ID'd by the DTC. If the fault is not in the trans wiring harness, it is between the transmission harness and the TCU. Why do you believe the trans wiring harness was replaced with the VB? Are you sure? Since you have replaced the VB and trans harness?, the only possible cause remaining is the wiring between the trans harness and the TCU. If the fault can't be located, new wires from the TCU to the trans harness need to be run on the outside of the main wiring harness to bypass the faulty wiring to Solenoid A. "Shift Solenoid A Performance or Stuck Off" As in Stuck off, Not receiving any control voltage from the TCU.

The wire for the control voltage to solenoid A, N88 is from TCU pin 30 to trans harness connector T16g/8 (harness connector T16g, Black 16 pin connector, pin #8, at trans case.) 0.5mm diameter Green/Brown wire color.

sorry for not specifying. I was only talking about the valve body harness

[diagnosticator]

sorry for not specifying. I was only talking about the valve body harness

Right, the harness from the VB solenoids to the connector at the trans casing, T16g. The only wire remaining that can be faulty is the Green/Brown wire from the TCU to the transmission. That wire must be checked for an open circuit or short to chassis ground.

[zakx]

Right, the harness from the VB solenoids to the connector at the trans casing, T16g. The only wire remaining that can be faulty is the Green/Brown wire from the TCU to the transmission. That wire must be checked for an open circuit or short to chassis ground.

Hello, havent touched the car since. If I replaced my whole tcm harness will it fix the issue? Also, its not always having this issue so can it just be maybe a faulty tcm?