Xantia heater motor & heated rear screen

walnut · Post by **walnut** » 16 Nov 2005, 12:43

Please help
My Xantia 1.8td has an intermitant fault with the hedater motor & heated rear screen not working.
I have checked for loose wires, all fuses, earthing points near battery, shacking ingnition switch, all without success.
Read onthe forum about bypassing the ignition switch with a shunt relay, does anybody have the instructions for this repair?

AndersDK · Post by **AndersDK** » 16 Nov 2005, 14:47

Yep its the ignition switch playing up allright.

The repair is simply to control a standard make-relay by one of the still working ignition switch sections. Then using the relay's make contact instead of the knackered switch section. Very simple indeed. But very comprehensive to explain if you are not familiar with car electrics (and then a fire hazard too

).

Clogzz · Post by **Clogzz** » 16 Nov 2005, 15:20

The way I did it was to use the old switch contact and wire to operate a relay dangled inside the space above the passenger footwell.
I soldered a thick new fan supply wire before the ignition switch, and passed it behind the heater and ventilation controls to the relay via a 35 Amp fuse in an in-line fuse holder, and then from the relay to the fan motor.
The earth for the relay coil goes to a bolt on the metalwork inside that space, possibly a front guard mounting bolt.
The old switch contact is still good for the low current to operate the relay, but can't cope with the current for the fan motor.
It's been good for years ever since.

walnut · Post by **walnut** » 17 Nov 2005, 18:50

Thanks for the advise.
I have worked out which wire from the switch is not switching to 12volts, works sometimes so I can tell that the wire going to fuse 20 is not getting 12v.
I understand the circuit needed to bypass the ignition switch but the wiring diagram in the haynes manual is not very acurate, wrong wire colours, wire numbers and different circuit.
Does anybody know where I can obtain a more acurate wiring diagam?

Thanks again for the help, my taxi customers are desperate for a fix, the weather here is freezing and at 6am, without a heater it is not a nice situation.

Post by **RichardW** » 17 Nov 2005, 19:31

Here's a link to a thread where I explained how to do it, and posted a link to an excel file that shows the wiring diagram.

http://www.frenchcarforum.co.uk/forum/v ... hp?t=15671

Clogzz · Post by **Clogzz** » 18 Nov 2005, 12:14

This photograph shows most of what's involved.

Peter Mannn · Post by **Peter Mannn** » 18 Nov 2005, 13:58

I will email a comprehensive parcel of information on this procedure to those who ask. nicolewis@optusnet.com.au

nitro · Post by **nitro** » 20 Nov 2005, 00:42

Hello I had the same problem
I was wondering what was wrong but thanks to this forum(the andyspares one) I have been told that it was the ignition switch, I changed it with a good one; it is not difficult BUT you have to remove the steering wheel and obviously the airbag that is not a problem either putting the copper circles on the steering cloumn was the worst part I thought I did it properly but they touched and buggered the whole electrics in the car so becareful with that
good luck

walnut · Post by **walnut** » 23 Nov 2005, 22:20

Thankyou Peter for the info, diagrams.
Xantia nice and warm inside now, customers teeth have stopped chattering.