Rear Lights
Rear Lights
1994 850 non turbo. I was recently pulled over because the brake lights weren't working. I discovered the fuse had blown and replaced it. after replacing the fuse this began.
When I apply the brake, my right hand blinker illuminates solid both front and back and there is a constant 12v going to the harnesses. With out the brake the turn signal operates normally. When the turn signal is on and I apply the brake it illuminates solid. The brake light operates normally and does not blink with the signal switch. This tells me there is a short between the brake switch at the pedal and the blinker circuit. but where.
Looking at the wiring diagram it seems that there could be an issue at the rear bulb failure sensor. any other suggestions on where to look would be greatly appreciated.
When I apply the brake, my right hand blinker illuminates solid both front and back and there is a constant 12v going to the harnesses. With out the brake the turn signal operates normally. When the turn signal is on and I apply the brake it illuminates solid. The brake light operates normally and does not blink with the signal switch. This tells me there is a short between the brake switch at the pedal and the blinker circuit. but where.
Looking at the wiring diagram it seems that there could be an issue at the rear bulb failure sensor. any other suggestions on where to look would be greatly appreciated.
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Joined: Mar 2009
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From: Albuquerque, NM
Maybe you have a bad bulb somewhere. The 900 series have a problem with bulbs going bad and causing weird problems like that. Take the blinker bulbs out and make sure you don't have dual element connectors crushed together.
So I cut the Yellow wire from the brake switch to the rear bulb failure sensor no brake lights, but blinkers worked appropriately. I then cut the rear brake light wires coming out of the bulb failure sensor (ylw/gry, blk/gry, ylw/brn) and connected them to the brake switch wire (ylw) bypassing the bulb failure sensor. The problem came back. Then I disconnected each of the brake lights one at a time from the power coming from the brake switch. when the center brake light was disconnected the problem stopped. so... the wire from the center brake light is the culprit. I put a new bulb in for the third time and it still was not working right. I checked the ground still not working. I checked wire from failure sensor to the light now shorts, however, the tow bar bypass relay was spliced into it for trailer brake lights. I disconnected the tow bar bypass relay and voila. brake lights and blinkers at the same time with no issues. I guess the next time I want to tow something I will have to deal with the trailer wiring then.
So I cut the Yellow wire from the brake switch to the rear bulb failure sensor no brake lights, but blinkers worked appropriately. I then cut the rear brake light wires coming out of the bulb failure sensor (ylw/gry, blk/gry, ylw/brn) and connected them to the brake switch wire (ylw) bypassing the bulb failure sensor. The problem came back. Then I disconnected each of the brake lights one at a time from the power coming from the brake switch. when the center brake light was disconnected the problem stopped. so... the wire from the center brake light is the culprit. I put a new bulb in for the third time and it still was not working right. I checked the ground still not working. I checked wire from failure sensor to the light now shorts, however, the tow bar bypass relay was spliced into it for trailer brake lights. I disconnected the tow bar bypass relay and voila. brake lights and blinkers at the same time with no issues. I guess the next time I want to tow something I will have to deal with the trailer wiring then.
I call it the process of elimination or just lucky.
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