Rglrts
Member
Hi all,
I've just bought a 2005 Wagon with only 85,000 miles on it. She's a real creampuff, driven by a grandpa and serviced on a regular basis. But naturally, it is showing the p0741 code. I borrowed a VAGCOM and did some preliminary checking, and other probing.
The car will drive a few miles, until the tranny is up to 70C, and the TC will lock up. Temperature will eventually go to 95C (too hot?). After 70C, I start losing lockup in 5th, then 4th, then 3rd. When it's warm enough, no lockup, but the tranny shifts fine. When the TC is locked up, there is no slippage.
Here's what I checked:
1) Fluid and filter was changed at 50,000 miles, and was full and clean.
2) TCM is clean and dry.
3) Wire loom has perfect continuity to transmission solenoids and sensors.
4) All 6 solenoids pass ohmmeter test
5) The TOT (transmission oil temp) was within tolerance
6) The OSS (output speed sensor) was 3x the tolerance recommendation
7) The TSS (turbine speed sensor, also called the input speed sensor) was way out, basically open circuit
8) I tapped onto the EDS4 wires and verified that no signal is being sent to engage the TC clutch
If the OSS or TSS (or both) sensors are faulty, wouldn't the normal shifting operation be messed up? And there were 2 different versions of the TSS sensor used, one was a hall effect sensor, and may have a different tolerance than was in my spec book.
Any ideas?
I'm not a VAGCOM expert, and am back in a TDI since I sold my B4 wagon 15 years ago. So be gentle with me
Thanks, Bob
I've just bought a 2005 Wagon with only 85,000 miles on it. She's a real creampuff, driven by a grandpa and serviced on a regular basis. But naturally, it is showing the p0741 code. I borrowed a VAGCOM and did some preliminary checking, and other probing.
The car will drive a few miles, until the tranny is up to 70C, and the TC will lock up. Temperature will eventually go to 95C (too hot?). After 70C, I start losing lockup in 5th, then 4th, then 3rd. When it's warm enough, no lockup, but the tranny shifts fine. When the TC is locked up, there is no slippage.
Here's what I checked:
1) Fluid and filter was changed at 50,000 miles, and was full and clean.
2) TCM is clean and dry.
3) Wire loom has perfect continuity to transmission solenoids and sensors.
4) All 6 solenoids pass ohmmeter test
5) The TOT (transmission oil temp) was within tolerance
6) The OSS (output speed sensor) was 3x the tolerance recommendation
7) The TSS (turbine speed sensor, also called the input speed sensor) was way out, basically open circuit
8) I tapped onto the EDS4 wires and verified that no signal is being sent to engage the TC clutch
If the OSS or TSS (or both) sensors are faulty, wouldn't the normal shifting operation be messed up? And there were 2 different versions of the TSS sensor used, one was a hall effect sensor, and may have a different tolerance than was in my spec book.
Any ideas?
I'm not a VAGCOM expert, and am back in a TDI since I sold my B4 wagon 15 years ago. So be gentle with me
Thanks, Bob