Electrical fault various

[cliff89]

Hi guys looking for some help my 2009 focus titanium automatic has the following faults rear wiper + both front and back washers not work my reverse light and fog lights don't work either the heated screen switch stays continually illuminated and I have changed the gem unit as that's what I was being told that was the problem and it's made no difference does anyone have any clues? 

Thanks 

[Tdci-Peter]

On 28/06/2016 at 2:52 PM, cliff89 said:

the following faults rear wiper + both front and back washers not work my reverse light and fog lights don't work either the heated screen switch stays continually illuminated and I have changed the gem unit

Hi,

That is a very odd collection of faults. I can see why the GEM (Or BCM) was suspected, it looks like a common link, though in fact the reversing light does not seem to be controlled by the GEM, it is hard wired via a switch in the gearbox.

I have looked for common earthing problems, but a variety of earth points are used: Left & Right rear wheel arch, and Passenger side door pillar earth point, at least.

But I have noticed one common element, I think. It is the "Ignition overload Relay" and its fuse, F12. The front wipers and headlamps do Not come through this circuit. But all the items you gave Do come from it.

This relay (R8) and F12 are in the Engine bay fusebox (not the one inside the cabin). It should be near the battery. Fuses F11 & F25 are also involved, they supply power to the relay coil. This Relay should be on all the time the ignition is on.

There is a layout picture inside my fusebox lid. I can photograph it if needed.

Peter.

 

[Tdci-Peter]

Hi,

Just seen your earlier post. Wiring diagram for mk2/2a is available via this site. see:

I see you may have already checked R8 & F12, but it is worth re-checking these, or the wiring from here to the Passenger fuse box, the link is strong.

Peter.