Brake light check light lit but break lights are ok.

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Doobit
E30 Zone Newbie
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Location: West Sussex

Post Sun May 08, 2016 8:28 am

I have an intermittent fault when the break light check warning light comes on, but the break lights are ok.

Anyone have any ideas what this could be. Is it worth just changing the bulbs?
E30 325i Cabriolet Alpinweiß chromie
F12 640d
G11 730d
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Brianmoooore
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Joined: Mon Jan 10, 2005 11:00 pm

Post Sun May 08, 2016 2:51 pm

Common cause is an incorrectly adjusted brake pull rod - one of the few adjustments that needs to be made occasionally on an E30 to compensate for wear.
If the brake pedal has dropped far enough so that the brake light switch is on the point of putting the lights on, the lights will flicker on over pumps, and this can trigger the warning light.
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Doobit
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Location: West Sussex

Post Sun May 08, 2016 8:45 pm

Thanks Brian. I've checked the break pull rod, seemed OK I tightened it a bit, but the fault is still there. Does the fact that this happens most often when I start up and the car is stationary, then it goes away if I hit the break pedal make any difference to what you think it could be?
E30 325i Cabriolet Alpinweiß chromie
F12 640d
G11 730d
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Brianmoooore
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Posts: 49359
Joined: Mon Jan 10, 2005 11:00 pm

Post Sun May 08, 2016 9:16 pm

Doobit wrote: Does the fact that this happens most often when I start up and the car is stationary, then it goes away if I hit the break pedal make any difference to what you think it could be?
Yes, that does make a little difference! That's exactly what it's supposed to do - put the LED on at start up, then extinguish it the first time the brakes are used, if no fault is present.
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Doobit
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Posts: 146
Joined: Tue Apr 05, 2016 11:00 pm
Location: West Sussex

Post Sun May 08, 2016 10:23 pm

Brianmoooore wrote:
Doobit wrote: Does the fact that this happens most often when I start up and the car is stationary, then it goes away if I hit the break pedal make any difference to what you think it could be?
Yes, that does make a little difference! That's exactly what it's supposed to do - put the LED on at start up, then extinguish it the first time the brakes are used, if no fault is present.
Thanks Brian, next time I'll read the manual properly!
E30 325i Cabriolet Alpinweiß chromie
F12 640d
G11 730d