Ford Focus (1998 - 2004) - 00 1.8 Heated Rear Windscreen Fault

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Sat 14 Nov 2009 18:08
00 1.8 Heated Rear Windscreen Fault - brodington
I have recently purchased a 1.8 Zetec, its great but the heated rear screen (and mirrors) won't heat.

When I press the button the light comes on but goes off straight away. There is also a click from the relay in the glovebox.

I have changed the relay and the relevant fuses but it still doesn't work!

(I dont think its connected but the air recirculation does not work either.)

I have searched the net and this forum and cannot find a solution. Any suggestions as to what I can try next to resolve this?

Edited by Pugugly on 14/11/2009 at 22:07

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Sat 14 Nov 2009 21:58
00 1.8 Hearted Rear Windscreen Fault - elekie&a/c doctor
The hrw and all the other timed functions(wiper ,interior light delay,etc)are controlled by the gem module.Is the car fitted with heated front screen?The re-circ function may not be related,but will not operate if the heater distribution rotary control is set to defrost windscreen.As with anything electronic ,you could try disconnecting the battery to see if this restores the hrw operation.Also check under bonnet fuse box.hth
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Sat 14 Nov 2009 22:29
00 1.8 Hearted Rear Windscreen Fault - brodington
It does have heated front screen, which work fine (amazingly well actually!)

I'll try battery tomorrow and see if that helps, thanks for your input. It is very well recieved.
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Sun 15 Nov 2009 09:13
00 1.8 Hearted Rear Windscreen Fault - brodington
I tryed the battery disconnect and it didn't help.
Any other ideas out there, I am stumped. I have read somewhere about a timer module behind the glove box fuse box, but am I right in assuming that as other timed things (i.e. heated front screen) work fine this part if funtioning correctly? Ot could it be semi faulty?
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Sun 15 Nov 2009 09:34
00 1.8 Hearted Rear Windscreen Fault - elekie&a/c doctor
The timer module (gems unit)is above the accelerator pedal.It is a black plastic box with 5 or 6 multi-pin connector blocks that are locked in by yellow over-centre catches.May be worth a try to unclip and refit.I can dheck the wiring on Ford tech diagrams tomorrow.hth
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Sun 15 Nov 2009 15:10
00 1.8 Hearted Rear Windscreen Fault - brodington
I cannot see a 'gems unit' above the accelerator pedal, there is a 'central locking / security module' up there which looks like what you describe. Is that what you are meaning?

My Haynes manual says that the heated rear windows / mirrors are timed by the 'Central Timer Module' which is behind the glovebox fuse box.

The air recirculation DOES work as described above (whenever the air is not pointed at the screen!)

P.s. thanks again for your help.
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Sun 15 Nov 2009 18:28
00 1.8 Hearted Rear Windscreen Fault - elekie&a/c doctor
Early Mondeo models had a timer unit clipped into the back of the glove box fuse plate.As your car is an early Focus ,it could be the same .I,ll check tomorrow.hth
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Mon 16 Nov 2009 13:22
00 1.8 Hearted Rear Windscreen Fault - elekie&a/c doctor
Just to update the info .This model does have a timer unit that plugs into cabin (behind glove box)fuse/relay plate.Also check fuse #7 40amp in engine bay fusebox and k1 rear window relay in cabin fusebox.second row down,last location on the right.hth
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Mon 16 Nov 2009 20:03
00 1.8 Hearted Rear Windscreen Fault - brodington
Thanks for that. I have changed the relay that you mention. Should I just pull out the Timer unit, give it a 'technical blow' and push back in?

If the 40 Amp fuse was duff wouldn't I notice a few other electrical faults?
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Mon 16 Nov 2009 20:13
00 1.8 Hearted Rear Windscreen Fault - bell boy
dont worry about your radio code i can tell you that if you need it by pulling a wrong bit
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Sun 22 Nov 2009 11:47
00 1.8 Hearted Rear Windscreen Fault - brodington
OK i just removed the CTM, blew on it, then replaced and nothign has changed :(

So to recap - when I press the heated rear screen button, the light on the button flashes and there is a click from the relay in the glove box but no heated window...

I have changed the relevant fuses, relays and now checked the Timer Module (not replaced though).

Can anyone offer any advice as to what I should look at next? The car did have a huge football sticker over the rear screen before I purchased it and the garage removed it, could there be something going wrong at the screen itself?

Thanks for your help,

Neil
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Sun 22 Nov 2009 12:20
00 1.8 Hearted Rear Windscreen Fault - piston power
Is there a feed to the heated screen and a good earth?

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Sun 22 Nov 2009 12:53
00 1.8 Hearted Rear Windscreen Fault - elekie&a/c doctor
I think a bit more in-depth investigation is now needed with the aid of test light and digi-meter.The fact that the w/light comes on for a sec ,indicates that this could be a multi -timer fault.You could try a s/hand unit ,they are not coded to the car.The mirror heaters are fed from the same circuit from the relay but via a different fuse.hth
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Sun 22 Nov 2009 15:20
00 1.8 Hearted Rear Windscreen Fault - Ben 10
"but the heated rear screen (and mirrors) won't heat."

I have two focuses. I was under the impression that the heated mirrors worked from the heated front screen button.

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Sun 22 Nov 2009 15:47
00 1.8 Heated Rear Windscreen Fault - old crocks
Just checked Haynes wiring diagrams for Focus I,
Heated mirrors shown coming on with heated rear window.

( I had to check Haynes because I am never sure and just hit both buttons! )
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Sun 22 Nov 2009 16:00
00 1.8 Heated Rear Windscreen Fault - brodington
"elekie&a/c doctor" can you tell me what I should be testing?

Mirrors work with rear screen (except on mine where they dont work at all!)
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Sun 22 Nov 2009 20:10
00 1.8 Hearted Rear Windscreen Fault - Dynamic Dave
I have two focuses. I was under the impression that the heated mirrors worked from the heated front screen button.


As 99% of cars have heated rear screens (and very few cars have heated front screens), manufacturers wire heated mirrors up to the heated rear switch to save the expense of fitting a separate switch.
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Mon 23 Nov 2009 09:07
00 1.8 Hearted Rear Windscreen Fault - Ben10
Aren't the heated mirrors part of the climate pack, so include a heated front screen. If you don't have the heated front screen, then surely you wont have the heated mirrors.
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Mon 23 Nov 2009 12:07
00 1.8 Hearted Rear Windscreen Fault - 360
The heated mirrors work at the same time as the heated rear screen. I believe they are paired in this way because they both aid rear vison.
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Wed 14 Dec 2011 13:49
00 1.8 Hearted Rear Windscreen Fault - sammieL

hello, ive been tring to fix our windscreens which arent heating and have followed what i thought was advice from here but seem to have gone wrong somewhere as my stereo is now asking for a code, any chance i can get some help please??

id be most gratefull so i dont have to listen to my husband saying you should have let me do it any more....he still hasnt fixed the problem!!!

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