Wiper Switch Blows Fuse!

[Les Richards]

I’m in the UK and have a late 1985 Carrera 3.2 Targa Supersport RHD.

Could someone please help me sort the problem with my wipers, please?

Recently the wipers gave one wipe of the screen and stopped on the passenger side of the screen. The fuse had blown, as have subsequent replacements as I’ve tried to fix it.

If I take a direct 12v supply to the bulkhead socket (with the switch not fitted) I can get the wipers and washers to work OK. From this I deduced that these components were OK. As soon as I refit the switch and try it, the fuse blows.

On the recommendation of the PCGB technical expert I replaced the column switch with a s/h one that was guaranteed as being in good order but the problem persists. I appreciate that both switches could have the same fault but somehow that seems unlikely, I would have thought.

I’ve disconnected the delay potentiometer on the dash and also the washer pump but still the fuse blows. Occasionally, like this afternoon, I got the wipers to work on all speeds with the column switch connected but as soon as I tried the washers the fuse blew as the water hit the screen.

I am at a loss to know what to try next.

Any suggestions, please?