Brake light warning light

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Brucey
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Re: Brake light warning light

Post by Brucey »

IIRC a bad ground connection (quite likely if the control box was rusty before?) can result in some fairly erratic behaviour. If you have a DMM it may be worth measuring some ground wire resistances (eg on both the bulbs and the control box itself).

Alternatively measure the voltage of wires/connections that are meant to be ground wires, when the brake lights are on.

cheers
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maestro84
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Re: Brake light warning light

Post by maestro84 »

Brucey wrote: Wed Jul 18, 2018 11:03 am IIRC a bad ground connection (quite likely if the control box was rusty before?) can result in some fairly erratic behaviour. If you have a DMM it may be worth measuring some ground wire resistances (eg on both the bulbs and the control box itself).

Alternatively measure the voltage of wires/connections that are meant to be ground wires, when the brake lights are on.

cheers
Sorry for the late reply. The problem solved partially. I checked everythig around the rear lamps, tighted the mountings of the bulbs and the warning on the check panel went off. But a few days later it came back. Every time i start the car 50% of the time the light stays on. Otherwise the light goes off for the first press of the brake pedal but came back for the second and stays on till the engine is running. I dont know what to do.
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Brucey
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Re: Brake light warning light

Post by Brucey »

sounds like you still have a dodgy connection?

cheers
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maestro84
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Re: Brake light warning light

Post by maestro84 »

Brucey wrote: Fri Aug 03, 2018 10:14 am sounds like you still have a dodgy connection?

cheers
Yes but dont know where to look.
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Jono B good
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Re: Brake light warning light

Post by Jono B good »

Change to new bulbs and add dielectric grease. Sometimes bulbs are improperly working from China factories. Also swap in a new fuse for said application.
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sansouci
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Re: Brake light warning light

Post by sansouci »

Remember that dielectric grease PREVENTS current flow and is an insulator. You might consider Boeshield which is a spray-on protectant

https://www.theruststore.com/Boeshield- ... gKg8fD_BwE

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