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'75 right brake light wire color

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Old Jun 13, 2018 | 01:59 PM
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From: Tn
Default '75 right brake light wire color

Trying to chase down a no right brake light/turn signal condition on my '75 Coupe.. It's a dark green wire at the rear by the lights, internet research leads me to think it is also a dark green wire at the harmonica plug by the steering column? Can someone confirm that this is correct? I have juice on both sides of the harmonica plug on the dark green wire ( when brake is pressed),but no juice at the brake lights, and no juice in that wire around the right rear wheel well. Just want to make sure I'm chasing the right wire?
Thanks
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Old Jun 13, 2018 | 04:10 PM
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'75 schematic:
https://docs.google.com/viewer?a=v&p...WRiNTdjNjdkNTQ

Make sure that you have a good ground at that socket.
Run a wire to a good ground and the other end of the wire to the brass as shown.


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Old Jun 13, 2018 | 04:58 PM
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Thanks for the link to the schematic. I'll have to look at it tonight, it's too small on my phone😎😎. It's not a ground issue, I'm not getting power to the right rear brake light at all...... Must be a break or bad connection somewhere, just trying to figure out where......
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Old Jun 13, 2018 | 06:10 PM
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Confirm that you have power in and out of 'N' at the harmonica connection.




If good there then look behind the left kick panel and check for power in and out of the 12 point connector.

If good there remove the sill plate and check the wire for a break.
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Old Jun 13, 2018 | 06:21 PM
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Thanks, I've already checked the harmonica connector, good on both sides there. I didn't know there was a connector behind the kick panel, I'll check there next. I have found the correct wire in the harness behind the rear wheel in the cargo area, and no power there, so I do seem to be narrowing it down.
By "remove the sill plate" do you mean the chrome/aluminum plate at the bottom of the door opening? I pulled it this morning and there was just a fiberglass sill under it... Or is there another access point?
Thanks 👍👍
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Old Jun 13, 2018 | 06:32 PM
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The 12 wire connector is behind the plastic on the lower left where your foot would be if driving.
Yes, the aluminum sill plate has to come off first to remove the plastic part and there should be wires under it running to the rear.
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Old Jun 14, 2018 | 11:47 AM
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Thanks Peterbuilt!!!!! Seems it was a poor connection in the 12 wire plug. I've got both brake lights again. I did pull the sill plate again, and found the wiring harness just as you described...... I just didn't peel the carpet back the first time😳😳.
Anyway, Thanks again, Alton9
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