Brake/Tail Light Gremlin

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RocketFoot

Stangin' ain't easy but somebody gotta do it!
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Location
Latrobe, PA
My Car
1971 Mach 1
At a car cruise last night with the Mach1, we discovered that the brake lights are kinda messed up...it's hard to explain but her it goes:

Code:
Reference (how they should be) Rev indicates the center section of the 3 segment tail light lens where the reverse light is.
                           Left                            Right
Tail lights        (on) (rev) (on)              (on) (rev) (on)
Brake lights   (bright) (rev) (bright)    (bright) (rev) (bright) 


What is happening:
                            Left                           Right
Tail lights         (off) (rev) (on)             (on) (rev) (on)
Brake Lights   (bright) (rev) (off)       (bright) (rev) (bright)
Any ideas where to look? I don't think it is just a bulb because the inside tail light goes out when the brake is pushed. It should actually get brighter when brakes are on.

 
Check, bulb sockets / contacts

Socket ground wires

Gound wire to truck latch bracket

Don

 
I think this issue is resolved...we found a ground wire off on both sides. Put them back on the sockets and everything seems to be working now!

The only problem left to deal with is the brake lights stick on sometimes. Guess I have to find the brake light switch and pb blast it!

 
no, you need to pull the switch out and replace it. its easy its just above the brake pedal on the brake arm, pull the connector, pull the red pin, slide the switch out, take care to look at the assembly order don't loose the plastic bushings there are 2 one on each side of the switch.

slide one bushing on the shaft, slide the new switch into place place the other bushing, push the pin back in, then attach the connector, done.

worst case is you have to pop out the drivers side seat to make room to work under the dash should take you an hour max.

 
Good idea! Wonder if NAPA still stocks them? I still have to take the seat out anyway...it has a separation between the cloth and vinyl that need repaired at the local interior shop. Sounds like then would be a good time to replace the switch!

 
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