Clipper Cab 1990 Heater / Blower issues - on and off please help

Hi everyone, hoping someone can help with this issue.

My heaters/blowers work on 1/2/3 no problems, however they work for say 30 seconds then just stop. They might start working on their own again, might not. If i turn the lights on or stereo etc, they may jump into life.

Now i realise this sounds like an earth issue? correct me if wrong. I have replaced the earth from the battery to body, grounded gearbox, engine, rad etc with new cables.
Is there a way of running new ground and live cables directly for the heater/blower?? just to rule out interference from other electrical components?


Cheers

the heater wiring is very simple, you have the ignition feed from the fusebox to the switch then the rest of the wires come straight from the switch to the blower unit. i would try another switch,  mk2 golf ones fit

rubjonny said

the heater wiring is very simple, you have the ignition feed from the fusebox to the switch then the rest of the wires come straight from the switch to the blower unit. i would try another switch,  mk2 golf ones fit

I have read thread after thread on electrical issues here, and I just hoped that you would come along and give some input

Im going to trace all wiring to make sure its neat etc, and to isolate any issues there. Also to make sure someone hasnt "pinched" the power for the switch from another component.

Out of interest - does the fusebox on the car have a ground feed? Ive never looked previously. If it does I might replace this if easy enough with another ground source.

Thanks

the fusebox has an earth yes, if you look at the white D plug you'll see it. theres 3 large pins the one you ant has 2 chunky brown wires, one goes off into the engine bay to the wiper motor and the other goes to a female spade which pops into the white multi spade connection on a chunky brown wire that comes in with the lighting loom. you'll soon see what i mean!

its probably not that though if it was then everything else would be ropey not just the blower.

to bypass the blower switch get some chunky wire and bridge the red/black wire to all of the others 1 after the other, the blower will then work on the various speeds. leave the wire bridge in place for more than 30 seconds and see if it still cuts out. if not its blower switch, if it does its something else!

what happens is the fan works for approx 10-15 seconds, then slowly spins down until it has stopped. It seems to stop working quicker on 3 than it does on 2 1nd 1.
It isnt a complete stop, its like the fan works fine, but then gradually loses power until it stops altogether.

Ive ordered a new switch in case, but im guessing its going to be the fan / motor