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D2 - Transmission Gearboxes, diffs, drive shafts.

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  #21  
Old 4th August 2021, 05:49 PM
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johnny_quattro johnny_quattro is offline
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I checked my car using my OBD Eleven device on the OBD-II interface and it came up with a transmission control unit/module ROM checksum error at the time - hence my actions in getting the unit replaced despite it looking visually perfect.

John G
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  #22  
Old 4th August 2021, 06:27 PM
Simon Wallwork Simon Wallwork is offline
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Thanks John
I guess my TCU has had it too.

MikkiJayne. Reading through the threads on here in search of wisdom, I noted somewhere that you have a box of them
Would you consider flogging me one, please?

Mine is 4D0 927 156 BN

Ta.
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  #23  
Old 10th August 2021, 04:21 PM
Simon Wallwork Simon Wallwork is offline
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Got the codes read and up came "P0758 Shifter Solenoid B: Electrical".

What can cause this?

Is there a cable that could be damaged or nibbled by animals? (a known problem here)- or could it be low ATF level?

Last edited by Simon Wallwork; 10th August 2021 at 07:39 PM.
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  #24  
Old 10th August 2021, 05:16 PM
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Highly unlikely that low ATF would cause an electrical problem with one of the solenoids. Your suggestion of animals is probably more realistic, as I've read previously about how much damage is caused by them. A thorough inspection of the appropriate loom should confirm your suspicion, as well as checking the physical connection to the transmission to ensure it's clean and secure.
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  #25  
Old 10th August 2021, 07:36 PM
Simon Wallwork Simon Wallwork is offline
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Thanks Steamship.
Luckily I have a pit here, so will have a look tomoz.

The Pine Marten is a known nibbler, and if he has been at my car, I shall give him lead poisoning.
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  #26  
Old 23rd August 2021, 11:50 AM
Simon Wallwork Simon Wallwork is offline
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This turned out to be a faulty TCU.
A secondhand one has fixed the problem completely.

For info, my car was stored for about 18 months outside in Scotland, but it ran fine for 6 months this year after coming out of storage and shipping to Bulgaria..

The fault appeared out of the blue and became harder as time went by, putting the box into limp mode nearly every journey, but not 100% of the time.

In the end about one start in forty didn't result in limp mode, but the rest did.

I guess it was condensation inside the TCU while it was stored that was at the root of the problem.
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