1972 indicator and brake light issue

Classic Z

Club Member
Hi

I have been trying to fix the rear indicators with no success. Does anyone have any ideas?

The left indicator works but I do not know if it is normal that it flashes red (top left light flashes) as well as the white light which is lower right. Both flash. When I turn on the right indicator both sides flash (Right and left) but not the right side white light (lower left). This is odd. What's more, is that the right light is dim. If I remove one of the left flashing bulbs the right side is bright again. This is also odd. Both sides should not flash.

Where are the indicators on a 240z. Which lights should be flashing. The hazard lights do work so the hazard switch works.

Also, the brake lights do not work. The brake switch has been tested and seems fine. Which light panel is suppose to be the brake light?

Thanks

Paul
 

Rob Gaskin

Treasurer
Staff member
Site Administrator
You need a wiring diagram and an auto electrician. They need to follow the lighthing circuits and also check the 'ground' at the rear. I would start by unplugging the multiconnectors in the footwell and checking for power from the dash (for each circuit) and continuity to the rear for each wire to the bulbs.
 

johnymd

Club Member
My first thoughts are earth issues. A typical symptom of an earth issue is multiple bulbs are on instead of just 1. The reason is that one of the bulbs is finding its way to earth through another bulb so both light up but only half brightness. If the car hasn't been converted to UK style then the stop lights will flash as indicators.
 

Albrecht

Well-Known Forum User
There's a small earthing strap in the rear loom (near the RH rear lamp unit) on the inside of the car that sometimes gets detached or becomes corroded. Just a black wire with a brass ring terminal on it. I'd check that first.
 

uk66fastback

Club Member
Are you fitting UK-style orange flashers - in the UK you’re not supposed to have indicators and brake lights using the same bulb - but then with no MoT required, who’s gonna check?
 

Rob Gaskin

Treasurer
Staff member
Site Administrator
Just a thought:

I don't know the exact configuration of US units but make sure someone hasn't fitted single filament bulbs in a double filament bulb holder.

I know it shouldn't be possible during to the bayonet pin location but I've seen it done. It causes cross- contamination.

My neighbour fitted a single filament bulb in his rear light holder. I noticed when he drove down the street he flashed his headlights when he put his brakes on!
 

Classic Z

Club Member
Thanks.

Yes, have checked all the correct bulbs are fitted. Checked the earths and made a new earth which helped with the brightness.

Still can not find the problem with the brake light. We ran a wire directly from the switch to the wiring loom at the back and now the brake lights work but this is not a permanent solution. I am wondering if a relay is gone. Do the brake lights have a relay?

Also, when we turn on the left indicators, the left ones work. 2 bulbs on the left at the rear flash. However, when we turn on the right indicators both sides flash. Both the 2 left bulbs and 2 right bulbs flash. Again I am wondering if it could be the indicator relay.

Does anyone know where I can buy an indicator relay from?

Thanks
 

Rob Gaskin

Treasurer
Staff member
Site Administrator
I drew a circuit for the indicator and hazard circuits (they are dependant on each other). Have a search on the forum. The components are hazard switch, hazard unit, indicator switch, indicator unit.

See this Thread:

 
Last edited:

kenny mitchell

Club Member
You need a wiring diagram and an auto electrician. They need to follow the lighthing circuits and also check the 'ground' at the rear. I would start by unplugging the multiconnectors in the footwell and checking for power from the dash (for each circuit) and continuity to the rear for each wire to the bulbs.
Like Rob has said, you need a wiring diagram to trace out the cables to make sure they all go to the respective lamps, as I am an electrician I know the tedious troubles of testing & tracing wires on a vehicle can be, but patience is a virtue. You may have a bad connection or tracking across the lamp holders if they are badly corroded possibly.
 

toopy

Club Member
Check the connections on the hazard switch and any multi wire connector if there is one , i can't remember. Many years ago i had a problem and it turned out to be one of the wires from the hazard switch and nothing to do with the rear loom.
 
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