I've recently been out and about in the moggie for a couple of spins in the recent weather, and have noticed that my heater doesn't work when i turn my windscreen wipers on - this is clearly problematic if it's very rainy and very cold at the same time (which it's not at the moment thankfully!)
Was wondering if anyone knew a common fault that could cause this and how to fix?
Also - bonus question - how do i get at the piping that carries the hot air to the windscreen? I have a suspicion that theyve both come loose as theres no hot air coming out!
Assuming its a later car, the heater takes its power from a green wire that comes down from the back wiper switch. There must be a problem with the wiring there.
You need to remove both glove box liners, you will then be able to see the pipes that go to the demister outlets for the windscreen. Whilst the liners are out you should be able to access the switches, a torch and mirror on a stick are handy for inspecting the wires. The voltage stabiliser is screwed to the back of the speedo. If you have to remove the speedo to get at it there is a screw either side holding it in place, you only need to loosen them a turn or two then you can pull the speedo carefully out. I'm not sure that is your problem though.
Its not a problem with the stabiliser, the wipers just take their feed from the incoming side of the stabiliser.It could be a loose wire there though.
Does everything work independently but just not together?
Richard
Opinions are like people,everyone can be different.
yup -both work absolutely fine independently, it's only when i try and turn both the wipers and heater on that results in just the wipers working, and the heater turning off.
The Minor de-mist vents are not very good. Air like anything else will travel the easiest route and that is to the cab vents, the screen vents are very restrictive. Someone on here a while ago suggested to block some of the cab vent with a cloth or sponge so forcing more of the heated air to the screen and it works. So little comes out the screen vents it's hard to know if their working . Good luck finding the wiring fault and if all else fails you could try running an extra wire from the fuse box to supply the heater motor. Hope this helps.
As above - absolutely nothing to do with the voltage stabiliser. The wipers and the heater share a common earth - and most likely this is 'bad' and each is able to find earth through the other - but of course not when they are both in use at the same time. Seek out the earth (trace the Black wire from the heater) and I expect that's where the problem lies.
I believe both the wiper and the heater work by 'switching on the earth connection' -certainly that's how the wipers work - and I believe the heater is also switched on the earth cable. Look under the heater and trace the wires!
. Good luck finding the wiring fault and if all else fails you could try running an extra wire from the fuse box to supply the heater motor. Hope this helps.
