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Discussion Starter · #1 ·
Hi All,

Had my ST in for a service the other day and when it came back the cruise control and hill start seem to no longer work. The warning for the hill start assist seems to come on after maybe 15 minutes of driving. Before this, it seems to work fine. Meanwhile, the cruise control seems to just not work at all now.

Looking around, it sounds like this may potentially be an issue with the clutch/brake switch sensor. But if this had completely gone, i would expect the hill start warning to come on right away. So, is there any way to check if the 2 switches are working? Or am I barking up the wrong tree here and is there anything else that people can think of that might be the cause of this?

Cheers
 

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Premium Member
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Hi All,

Had my ST in for a service the other day and when it came back the cruise control and hill start seem to no longer work. The warning for the hill start assist seems to come on after maybe 15 minutes of driving. Before this, it seems to work fine. Meanwhile, the cruise control seems to just not work at all now.

Looking around, it sounds like this may potentially be an issue with the clutch/brake switch sensor. But if this had completely gone, i would expect the hill start warning to come on right away. So, is there any way to check if the 2 switches are working? Or am I barking up the wrong tree here and is there anything else that people can think of that might be the cause of this?

Cheers
First step is definitely a code scan via ODB. Is anything being thrown?
 

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Discussion Starter · #3 ·
First step is definitely a code scan via ODB. Is anything being thrown?
Finally got round to reading my codes this morning (been away, then my laptop blew up so been a bit of a saga).

Forscan shows three codes:

PCM = P0504:23-2f - brake switch A/B correlation (signal stuck low)
PCM = P0504:64-2f - brake switch A/B correlation (signal plausibility failure)
ABS = C0040:64-68 - brake pedal switch A (signal plausibility failure)

All of the above point to the brake pedal switch. Guessing it will need replacing. Anyone know the part no i will need and if it is an easy job? Always hesitant to mess around with brakes.

Cheers
 

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Finally got round to reading my codes this morning (been away, then my laptop blew up so been a bit of a saga).

Forscan shows three codes:

PCM = P0504:23-2f - brake switch A/B correlation (signal stuck low)
PCM = P0504:64-2f - brake switch A/B correlation (signal plausibility failure)
ABS = C0040:64-68 - brake pedal switch A (signal plausibility failure)

All of the above point to the brake pedal switch. Guessing it will need replacing. Anyone know the part no i will need and if it is an easy job? Always hesitant to mess around with brakes.

Cheers
Maybe this one:

583645



 

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Discussion Starter · #5 ·

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So just thought I would post back again having now fixed it. Ordered the part and took all of about 10 mins to fit and now everything is working again.

Cheers for the links and part number help, much appreciated.
Glad you got it sorted 👍
 

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Discussion Starter · #9 ·
So bad news on the brake switch front. After working for a couple of days, it seems like the new switch has gone as well. Seeing as that's two switches in short succession, it points to perhaps something elsewhere that is causing the switch to fail. Anyone come across this issue before?
 

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Discussion Starter · #10 ·
Bump to see if anyone has any ideas before I order another switch and hope for the best. If that goes after installing then I guess at least I will know there is a problem elsewhere is causing it and then the fun of chasing electrical issues begins...
 
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