Brake fluid warning light not checking on start up

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ThreeDLee
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Post Mon Oct 19, 2015 8:08 am

Right this is strange, my e30 preface lift fluid light dose not want to check on start up with the rest of the lights, the light is working when I touch the two terminals together from the tank the fluid is held in but just don't check on start up?!

Can someone help?

Thanks.
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Brianmoooore
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Post Mon Oct 19, 2015 9:58 am

Is this the only warning light on your car that does a start test?
The circuit that performs the test is part of the SI board in the instrument cluster, and is activated by 12 volts appearing on the small blue wire from the alternator.
The actual fault can be a problem with the SI board, or ripple on the 12 volts from the alternator, caused by a faulty diode in the alternator confusing the SI board.
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ThreeDLee
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Post Mon Oct 19, 2015 11:12 am

Thanks for the reply mate!

I have just put another clock in and all the lights work but not I have to rev the car for the battery and pad ware light to go out on dash.... Sounds like a weak signal from somewhere.


Thanks
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ThreeDLee
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Post Mon Oct 19, 2015 11:16 am

If you leave the hand brake off so don't use you that light on dash they all come on and go off fine.

I think it's a signal problem...

Change alternator?
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ThreeDLee
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Post Mon Oct 19, 2015 11:18 am

Lazy temp gauge too