Back up Lights don't work on my '72 Satellite

Hello there,
I wondered if anyone can help me. I have just got my Satellite and the back up lights don't work. I have replaced the sockets/bulbs and gone through the rear harness for the lights. I have checked the fuse box. All is good now on that front but now I'm at a stand still. Any ideas where I should go next.
Many thanks

nurtal safety switch at the tranny.

Check to see if your getting power to the sockets when you have the gear in reverse no need to have car running and set the E-brake (safety thing) have a partner jiggle the gear shift to see if the setting is maladjusted where the probe light may illuminate indicating an adjustment needs doing.

Yep check the switch. The connector usually has come off or is bad. May be the switch itself too.

Thanks very much for all your replies, will let you know how I get on.

Looks like it was the switch and connector! both didn't look good so I have ordered new ones.

jumping out both black wires ( outer ends ) at plug with key in RUN or ACC should give you back up lamps light on... if not, problem comes from inside

I will give that a go first. The one I’ve ordered is in the picture, so just to be certain, connect the purple and black wires?

Purple and black are the ones what handle the positive source for the back up lamps. To make it correctly, black should be hot coming from fuse box in ACC and RUN, while violet is the output from NSS to lights, and of course just hot when tranny is in Reverse. Both wires could be spliced backwards and will work the same anyway, but just saying to make it correctly. That violet code was used since 75 or 76, because on earlier years color codes where both black, but one of them traced white. The black would be still the HOT source from fuse box and the black traced the one running to reverse lights. Those wires becomes white into the cab, and the traced one is with black trace. Becomes violet into the rear lighting harness ( at kick panel plug ).

Brown wire with the yellow trace is the ground to Starter relay and also to the seatbelts warning system since 72.

Honestly, on this harness I would replace the full harness if needed. Due the exhaust heat and oil, the section usually damaged is larger than just the conector pigtail. Aside the conector price is on $15-20 rate and the full harness price can be on $30 rate, so the full harness could have been a better option for the price.

Next time when you join a forum, instead of just jumping in and asking for help, introduce yourself first. There are several options on this forum for that sort of thing.
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