Brake check light

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BenHar
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Post Sun Mar 02, 2014 5:06 pm

I spent the weekend fitting an OBC and cruise control to my 1990 325i cabriolet.

It all seems to be working but the brake check warning light does not go off when I apply the brakes.

The brake lights are working and the cruise disengages when I brake.

I have tried unplugging the cruise control's brake connection to the accessory socket but it has no effect on the warning light.

Any ideas, please?

Thanks
Ben
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Post Sun Mar 02, 2014 7:18 pm

Are the brake lights working?
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BenHar
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Post Sun Mar 02, 2014 9:53 pm

daimlerman wrote:Are the brake lights working?
BenHar wrote: The brake lights are working and the cruise disengages when I brake.
Ben
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BenHar
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Post Mon Mar 03, 2014 4:10 pm

Brian, Have you got any suggestions?

Thanks
Ben
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Brianmoooore
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Post Mon Mar 03, 2014 6:41 pm

I doubt if it's anything to do with the cruise control fitting.
Check that both brake lights are of equal brightness, and if possible, get someone to follow you while you drive to see if the brake lights do exactly what they should.
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Post Mon Mar 03, 2014 6:51 pm

Brianmoooore wrote:I doubt if it's anything to do with the cruise control fitting.
Check that both brake lights are of equal brightness, and if possible, get someone to follow you while you drive to see if the brake lights do exactly what they should.
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BenHar
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Post Mon Mar 03, 2014 7:10 pm

Brianmoooore wrote:I doubt if it's anything to do with the cruise control fitting.
Check that both brake lights are of equal brightness, and if possible, get someone to follow you while you drive to see if the brake lights do exactly what they should.
Will do, Brian, thanks.

The cruise control introduces a couple of extra switches/paths to the brake light circuit which made me suspect that. I'll check the lights and clean all the contacts.

Thanks for your input, too, Malc.

Ben
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BenHar
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Post Sun Mar 16, 2014 5:29 pm

Fixed this today.

Above the glove box there is a loom connector with two wires, a large red/yellow and a small black/green. The black/green was cut (black/green is the feed from the overhead check pabel to the rear lights check relay at the rear).

I must have cut the wire somehow when refitting all the trim panels.

Ben