Check brake light warning when lheadlights are on and wipers turn on

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PattheCat
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Post Mon May 24, 2021 10:17 am

Hi guys, got a weird problem that I'm wondering if any of you have faced.

When my headlights (or sidelights) are on and I turn on the wipers, the check brake lights warning pops on. As soon as I touch the brake pedal it disappears. I know electric issues are a PITA to diagnose but some suggested start points would be appreciated
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Brianmoooore
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Post Mon May 24, 2021 1:34 pm

I think you have a unique one here, but when you get interaction between completely different systems, the earthing points are the first thing to check, and the only way I can make any sense of what might be happening is if there are two separate faults.
Check (dismantle, clean and reassemble) the earthing point on the front of the LH inner wing, the earthing point at the LH side of the rear seat pan, and the plug/socket connections for the rear lamp holder assemblies.
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PattheCat
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Post Mon May 24, 2021 4:57 pm

Thanks Brain, I have a real newbie question that you will most definitely know the answer.

Since Ive had the car everytime I start it, it has the check light flashing and the brake light bulb showing on the panel, but as soon as I press the brake pedal it disappears. I assumed this was itself checking that the brake lights were working but I'm starting to think this is probably related...
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BenHar
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Post Mon May 24, 2021 6:48 pm

PattheCat wrote:
Mon May 24, 2021 4:57 pm
Since Ive had the car everytime I start it, it has the check light flashing and the brake light bulb showing on the panel, but as soon as I press the brake pedal it disappears. I assumed this was itself checking that the brake lights were working but I'm starting to think this is probably related...
That is correct behaviour.

The check light and brake warning should go out the first time you touch the brake pedal after starting.

(It's all in the handbook.)

Ben
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Brianmoooore
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Post Mon May 24, 2021 6:53 pm

^^^^ What Ben wrote^^^^
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PattheCat
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Post Mon May 24, 2021 6:58 pm

Thanks for confirming Ben, I did think this was correct but started doubting myself!

I can get it to trigger when just using the wipers regardless of the lights being on so at least that narrows it down a little.

Will check the ground like suggested and update this post when/if I find the problem in case some other unfortunate soul has the same problem