"brake light (!)" bulb comes on....

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E30_320i
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Post Sun May 22, 2005 3:40 pm

hi ppl

the "brake light (!)" red bulb comes on the overhead computer when i turn ignition/start car. i know that you have to press the brake pedal for it to go off. so i do so and it goes off...

then after 10-15 mins it comes back on again with the "check" light flashing in the middle of the two clocks.

now ive checked the brake lights and they work fine, so what could be causing this problem???

also the "engine oil" red bulb came on the other day when i started the car but there was plenty of oil in when i dipped the stick. and my grandad said that this happens from time to time??? but the lights gone off now so its fine.

my main concern is though that the "brake light (!)" bulb seems to come on after 10 minutes of driving :?

Lee
elliot
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Post Sun May 22, 2005 3:46 pm

you may have a dodgy switch which is located on the foot pedal. if the contacts are going it will probably happen every so often. its worth a change as they only cost a couple of quid.

as for the oil light, are you parking on a hill? mine does this if im parked on a steep incline.

elliot
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E30_320i
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Post Sun May 22, 2005 4:02 pm

cheers for the reply elliot, yeah i was parked on a hill at the time lol.

ill go outside now and check the contacts.

Cheers

Lee
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Brianmoooore
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Post Sun May 22, 2005 8:30 pm

Oil level warning you seem to have solved.
For the brake light warning, change the rear brakelight bulbs for a couple of good quality ones, and see if that helps.
Some bulbs of dubious origin are well out of spec as regards current consumption, and can fool the bulb sensor into thinking one is blown.
You do mean the red LED near the rear view mirror and the flashing "check" in the middle of the instrument panel, don't you, and not the red (!) warning light in the row at the bottom of the instruments?
This light refers to low brake fluid level in the resevoir.
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E30_320i
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Post Sun May 22, 2005 8:34 pm

yes brian its the check panel near the rear view mirror and the check light flashes in the middle of the instruments, i noticed there was 1 bulb which was a bit smokey/black inside, this might be the 1 causing the bother you think??

Lee
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Brianmoooore
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Post Sun May 22, 2005 9:23 pm

The blackening on the inside of the bulb is caused by the filament being deposited on the inside of the glass, and getting thinner as it does so.
The brake lamp monitor is looking for a current of 1.75A from each brake light. If this drops below a certain level, then the check control will indicate a bulb failure. The ageing bulb could be drawing a current less than this, or it could just be a dubious lamp in the first place. Could also be tarnished lbulb contacts or holder.