Electrical gremlin

virago72, Aug 19, 4:39pm
Hey guys and girls. I've got a 79 HZ panel van and I'm experiencing a small electrical issue. When I turn key on, drivers side rear only, indicator lights up. It flashes as normal when I turn indicator on but then stays on when I turn indicator off. How is this getting power? and why only the rear indicator? as I would have thought front and rear would be connected? Any ideas, advice would be appreicated.

taipapaki, Aug 19, 5:21pm
Pull the flasher relay (or fuse if its all that's on it) out.

If the permanently lit lamp goes out, its getting its hot from the indicator circuit.

Faults likely to be in the indicator switch, or maybe hazard light switch if it has one.

If it doesn't go out, the hots coming from another circuit - probably something to back like fuel pump, pull fuses till you find which one, then look for a short etc.

Always check bulbs are correct type and wattage, and earths are good when trying to track down weird shit like this too, as a lamp can find an earth via another lamp(s) filament, and you may not see the other lamp(s) glow.

virago72, Aug 19, 5:52pm
Cheers mate. Pulled flasher, lights went out. Pulled fuses one by one. Turned out to be the dash warning light fuse. Had power in and 2 wires out, not sure why 2 wires. Tried them individually, first one did nothing I could see, so not sure where that goes at this stage. Indicator getting power from wire for dash warning lights, not sure how or why. Have pulled fuse for now. Next question is do I need dash warning lights for WOF? Lights are for oil,volts and handbrake? Hopefully not. Cheers again

msigg, Aug 19, 5:56pm
Probably not, the one they look for is abs which you don't have. Otherwise leave it running and say your battery is flat so don't turn off please. All good.

intrade, Aug 19, 5:59pm
it be getting power via a other circuit The problem might be in the light including potentially the bulb.
There is a case study how a car stalls at red lights when brake pressed .
in this case the ground wire of the pump was bad and it used the lightbulb as a ground . but when you press the brake the light illuminates and it uses its ground and the pump ends up without a ground and dies . and so did the engine after few secounds.

its probably something similar with your symptom description.

taipapaki, Aug 19, 6:28pm
Dash warning light circuit might power the lamps that show your indicators are on (the indicators that indicate your indicators are indicating). so that may be a clue.

poppy62, Aug 19, 7:40pm
Just a different opinion. Have you got a trailer/towing plug unit? It could be that a short in this could be sending power back to the R/R Ind light, this would be because the trailer/towing plug takes it's power source from the rear light units. My opinion only.

jmma, Aug 19, 7:42pm
I would check the reverse light switch circuit also as that only powers up the rear indicators. so maybe something there?

budgel, Aug 19, 10:08pm
Check all earths too. Weird backfeeding can be caused by this.

bigfatmat1, Aug 19, 10:18pm
Dont they have that weird reverse light switch with at bottom of steering column. (before my time) They always crap out it also has indicators going into it. could check that.

taipapaki, Aug 20, 7:34am
Good thinking - some of these cars used the indicators as reverse lights if my memory serves me right.

virago72, Aug 20, 4:46pm
hmmmm yeah with fuse for dash warning lights out the reverse lights dont work. Going to have to keep searching I guess.

snoopy221, Aug 20, 4:49pm
Yeah going way back but seem to recall a couple of diodes in that system.
With fuse in check that BOTH reverse lights work.

virago72, Oct 20, 10:07pm
Got it sorted! Cheers for all the comments. Plug on bottom of steering coloumn weren't making a good earth contact. All going now as it should. One happy chappy