Help with tc and hill descent amber lights

Cocker2020 said:

Hi all , tearing hair out right now with tc and hill descent lights on which also cuts power to fuel so no start.
Just sometimes lights decide to go out and hey presto , fuel pump works and starts right away . switch off and leave for a while and they come back on and no start up again . we have been working around handbrake tensioner (centre console ) . I know a lot of posts suggest brake light switch but haven't found anyone that complains of non starting when these two lights are illuminated.

Any help would be great

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GrumpyGel said:

I presume this is an auto?

When I saw that you had the 3 Amigos (I presume the ABS light is lit also as it should when ignition is turned on) and that the car would not start - I presumed they were separate issues as 3 Amigos doe not stop the car from starting.

However, an auto will inhibit starting if the car is not in park or neutral.

The ABS system uses inputs to determine if the vehicle is in 1st or reverse (for HDC).

Presumably therefore your issue is relating to which gear the vehicle believes you are in. I'm more familiar with the manual gearboxes and these are sensors on the box - however with the auto it may be within the shift mechanism/electronics.

Maybe someone else might have more ideas.

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GrumpyGel said:

The bulb for the ABS warning has broken - or (much more likely) been removed to cover up an ABS issue - as it should illuminate when you turn the ignition on.

For the engine to crank, the immobiliser thinks all is OK (or the wiring to the starter has been frigged) - but for the pump not to activate presumably means the engine's ECU is imobilised or not seeing the ignition. For it to coincide with Amigos, I imagine there is a problem with the car's comms network.

Probably worth getting the diagnostic codes read - from engine and ABS module, it may tell you what's up, but if it is a network issue I could imagine the codes may be a red herring.

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Cocker2020 said:

Hi , I have no abs light and is a manual , if I turn on ignition and lights go out , we can hear buzzing fuel pump and it starts , however if 2 lights are illuminated , no sound and cranks but nothing.

Thanks for reply

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GrumpyGel said:

The bulb for the ABS warning has broken - or (much more likely) been removed to cover up an ABS issue - as it should illuminate when you turn the ignition on.

For the engine to crank, the immobiliser thinks all is OK (or the wiring to the starter has been frigged) - but for the pump not to activate presumably means the engine's ECU is imobilised or not seeing the ignition. For it to coincide with Amigos, I imagine there is a problem with the car's comms network.

Probably worth getting the diagnostic codes read - from engine and ABS module, it may tell you what's up, but if it is a network issue I could imagine the codes may be a red herring.

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Cocker2020 said:

Hi , still no joy , problem seems to be permanent now instead of intermittent , have tried to read codes but on set up it gets as far as ios90141 (or something like that) and displays link error .
Wondering whether to try replacement ECU or just plonk a brake light switch in to try . I'm quite stumped now .
Like yourself , interrupted power to fuel pump coinciding with lights is confusing and throwing me about.

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Cocker2020 said:

Hi , we managed to get OBD2 connection and returned no codes which we erased anyway and fuel pump started to operate .
We have now got all 3 amigos and no Speedo .
In the old days this would suggest faulty wheel sensors so will start looking at this from fuse , relay etc .
Could this still point to a brake pedal switch sending me on a goose chase...what do you think guys?

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