ABS/ESP Error C1391

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ragingraven
Posts: 16
Joined: 29 May 2023, 21:32
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Re: ABS/ESP Error C1391

Unread post by ragingraven »

Just replaced my accelerator pedal, was thinking that it could be causing the problem.
Got one from Poland from Toyota Proace II, it has the same one. Also changed crankshaft position sensor.
No luck, the problem still persists.
Coco83
New User
Posts: 1
Joined: 08 Aug 2024, 18:26

Re: ABS/ESP Error C1391

Unread post by Coco83 »

Did you solve the problem ?

I have same code c1391 no other fault codes showing and esp light on deactivated . Banging my head trying find the issue
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GiveMeABreak
(Donor 2016)
Posts: 41989
Joined: 15 Sep 2015, 19:38
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Re: ABS/ESP Error C1391

Unread post by GiveMeABreak »

You'll need to have it properly diagnosed - I've already put up the fault descriptor on the previous page - there's no magic cure as your issue may be different to the previous poster; it needs investigating and the suspect areas are listed at the end.
Please note, I'm no longer active on the Forum, so won't respond to messages.

Marc
malc4
Posts: 63
Joined: 17 Jun 2024, 12:39
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Re: ABS/ESP Error C1391

Unread post by malc4 »

My friends 308sw DV6C 9HR has just started throwing this fault after a leak-off pipe failure/replacement (and front tyre change at same time). I'm guessing it could be due to contamination of a brake sensor with diesel from the leak (or possibly the crankshaft sensor? same side as leak) .The wire down to the brake sensor is wet..

Is there any live data that would help diagnosis?
malc4
Posts: 63
Joined: 17 Jun 2024, 12:39
x 3

Re: ABS/ESP Error C1391

Unread post by malc4 »

Update to my C1391. Fuel was running down crankshaft sensor wire into connector. Cleaned it out with brake cleaner and fault hasn't returned as yet.
malc4
Posts: 63
Joined: 17 Jun 2024, 12:39
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Re: ABS/ESP Error C1391

Unread post by malc4 »

Seems lots of issues can trigger the ABS/ESP light. Yesterday *my* car had this code, but this time it was a failed injector that triggered it i think;(
shtu
(Donor 2023)
Posts: 226
Joined: 09 Dec 2023, 16:19
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Re: ABS/ESP Error C1391

Unread post by shtu »

One to add to the list of possibilities on the C4, is that the hub corrodes underneath where the ABS sensor is mounted, which forces it away from the bearing and abs ring, and can cause problems.

If that's the problem, the solution it free. Unblot the sensor, chisel and scrape all the corrosion out, refit.
ragingraven
Posts: 16
Joined: 29 May 2023, 21:32
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Re: ABS/ESP Error C1391

Unread post by ragingraven »

Finally fixed the error after 3 years.
Colleague suggested I check vacuum tubes, so I went around with small brake bleeding kit.
I think it was something to do with turbo vacuum lines, not sure.

So far 3 months and the error has not come back!
Mahmut +
Posts: 6
Joined: 16 Apr 2026, 06:27

Re: ABS/ESP Error C1391

Unread post by Mahmut + »

Which vacuum tubes did you check? Could you send a photo if you have one? I have the same error code.
ragingraven
Posts: 16
Joined: 29 May 2023, 21:32
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Re: ABS/ESP Error C1391

Unread post by ragingraven »

Mahmut + wrote: 21 May 2026, 21:10 Which vacuum tubes did you check? Could you send a photo if you have one? I have the same error code.
Hey Mahmut, won't be able to tell you which specific tube. I just went around all vacuum tubes, so I'm not sure which one was causing the issue.
Used standard brake bleeding kit, there was probably air where should have been complete vacuum. So far still no other problems have arisen. Car drives perfectly and doesn't stutter when going past 3500+ RPM.

Cheers and good luck!