A4 Shifting Problem
Thread Starter
Instructor
Joined: Sep 2022
Posts: 117
Likes: 64
From: Sylvania, OH
A4 Shifting Problem
Helping a friend. 2002 base coupe A4. No mods other than CAI. Trans will not upshift until we let off gas. Downshifts fine. Doesn't matter what speed or RPM. No trans specific codes. Do have the following communication codes.
Left Door U1016 Loss of Communications with PCM
U1064 Loss of Communications with BCM
Right Door U1016 Loss of Communications with PCM
U1064 Loss of Communications with BCM
U1096 Loss of Communications with IPC
U1255 Serial Data Line Malfunction
Seat SCM U1016 Loss of Communications with PCM
U1016 Loss of Communications with PCM
There are other codes specific to each of those areas and TCS/ABS is bad. I did read that a bad TPS could cause the same symptoms but the voltages are all in line. Thanks for any ideas.
Left Door U1016 Loss of Communications with PCM
U1064 Loss of Communications with BCM
Right Door U1016 Loss of Communications with PCM
U1064 Loss of Communications with BCM
U1096 Loss of Communications with IPC
U1255 Serial Data Line Malfunction
Seat SCM U1016 Loss of Communications with PCM
U1016 Loss of Communications with PCM
There are other codes specific to each of those areas and TCS/ABS is bad. I did read that a bad TPS could cause the same symptoms but the voltages are all in line. Thanks for any ideas.
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
First, check the transmission fluid level.
To do so, the car has to be raised. Fluid level is checked with the engine running, transmission in park after shifting through the gears. With the transmission temperature at 122 F on the DIC.
Do NOT remove the fill/ level check plug UNLESS the engine is running, transmission in park. Install the plug BEFORE shutting down the engine. If you shut down the engine with the fill/level check plug not installed, fluid will pour out and the transmission will be low on fluid.
To do so, the car has to be raised. Fluid level is checked with the engine running, transmission in park after shifting through the gears. With the transmission temperature at 122 F on the DIC.
Do NOT remove the fill/ level check plug UNLESS the engine is running, transmission in park. Install the plug BEFORE shutting down the engine. If you shut down the engine with the fill/level check plug not installed, fluid will pour out and the transmission will be low on fluid.
Thread Starter
Instructor
Joined: Sep 2022
Posts: 117
Likes: 64
From: Sylvania, OH
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Thread Starter
Instructor
Joined: Sep 2022
Posts: 117
Likes: 64
From: Sylvania, OH