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| Brake lights not working (Page 1/5) |
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Cliff Pennock
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DEC 05, 08:39 AM
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In the continuing series of "Another day, another problem"...
My brake lights no longer work. The third brake light does work, just not the two other. I'm not at home so can't look at the schematics in the service manual.
But what could this be?
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theogre
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DEC 05, 11:27 AM
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Year model...
If gt all on same blue wire so something bad likely @ or after C500.
maybe Bad ground burried under right body.
Need volt meter or test light to see if blue wire @ the bulbs have power. Neg to car's frame.
Did you put new bulbs in? The sockets maybe crap. See cave lightbulbs for some example.
Should be 4 red taillights using 2057 but only Brake wired for Bright side, HL/parking to "dim" side.
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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave[This message has been edited by theogre (edited 12-05-2023).]
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82-T/A [At Work]
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DEC 05, 11:28 AM
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| quote | Originally posted by Cliff Pennock:
In the continuing series of "Another day, another problem"...
My brake lights no longer work. The third brake light does work, just not the two other. I'm not at home so can't look at the schematics in the service manual.
But what could this be? |
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Yours is an 87?
I seem to recall that this had something to do with either a relay or a fuse. The third brake light seemed to be wired differently (as you can obviously tell). If it's an 87, I can look in my service manual... shouldn't be a hard fix.
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theogre
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DEC 05, 11:37 AM
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| quote | Originally posted by 82-T/A [At Work]:
Yours is an 87?
I seem to recall that this had something to do with either a relay or a fuse. The third brake light seemed to be wired differently (as you can obviously tell). If it's an 87, I can look in my service manual... shouldn't be a hard fix. |
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No relays or fuses.
All brake lights GT or not uses same fuse.
Only 84 have relays to used 6 bulbs as turn/brake lights in the back.
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Raydar
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DEC 05, 12:05 PM
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| quote | Originally posted by theogre:
Did you put new bulbs in?
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I was going to suggest this. (It's also the easiest thing to check.)
I drove around in a car (Chevy Citation - company car) for several days that had "no brake lights". Come to find out, all the bulbs were bad.
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Cliff Pennock
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DEC 05, 04:03 PM
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Ok I'm home again and during the trip back I noticed the following:
- The third brake light is always lit, but will light up even brighter when I hit the brakes.
- None of the rear lights work. So not only the rear brake lights. Reverse lights do work, however.
- The rear side lights are lit very, very dim.
- Blinkers don't blink. If I turn on the blinker, only the front blinkers light up a little but don't blink.
I haven't changed any bulbs. Apparently, this happened a few weeks back as well but only briefly. My daughter was following me in her own car and she noticed that for a brief period, only the third brake light worked, But after a few minutes, everything was back to normal.
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Cliff Pennock
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DEC 05, 04:05 PM
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Oh, 86.5 GT (figured y'all knew that by now 😁)
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Patrick
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DEC 05, 05:01 PM
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| quote | Originally posted by theogre:
maybe Bad ground burried under right body.
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If it's not something obvious (and easy to check) like a blown fuse... then my guess would be a bad ground as well, located on the passenger side rear upper frame rail (accessed through the wheel well with the plastic liner loosened enough to bend out of the way).
| quote | Originally posted by Patrick Here:
I don't know if this could be of any significance... but there have been reports over the years of funky taillight behavior when the rear taillight harness ground becomes corroded and/or detached from the frame.
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theogre
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DEC 05, 07:23 PM
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Check Taillight ground but also every fuse.
Watch brake lights w/ HL On & Off because rear narkers On but Dim. (red lenses not very bright even when On @ 100%)
High Brake ground inside the cabin and other ground(s) or fuses have problems & trying another sneak path sim to cave page on this.
May also affect turn bulbs not turn On or just Not Blinking w/ iffy taillight Ground because not enough Load for the Blinker can.
86 FSM have light wiring spread out to several pages...
Taillight Red Bulbs uses both sides w/ "dim" side On w/ HL/Parking Lights On. (Editted post above.)[This message has been edited by theogre (edited 12-05-2023).]
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Cliff Pennock
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DEC 06, 05:22 AM
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I haven't checked the fuses yet (it's really, really cold outside) but I have good hopes it might be a fuse:
If I look at above schematics, the "FAN E" fuse might be the culprit. It also explains why my coolant fan is not running when I hear the engine bay fan come on.
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