After realising the horn would only sound intermittently, I checked the contacts in the switch. Everything was fine there.

I have also noticed the Door/Lamps check-lights on the dashboard flash for longer than any other Sapphire i've had. There is also a warning light which stays on for the front left headlamp.

(the headlamp and indicator work fine, apart from looking a little out of alignment).

 

I would suggest checking your earth wires then go from there.

 

They shud not flash they flash when they not getting a signal from the door sensor! I.e wire broke or unpluged! Check the big multi plug that goes in to the metal ecu like box behind the cubby hole that's above the passanger glove box! (4x4)

 

The whole display and fuel/washer light should all come on for a few seconds when the ignition is switched on then extinguish.

As said flashing means there is a problem with that part, i.e. open circuit so in your case as said the wiring is most likely at fault or the switch itself.

As to the headlight, assuming the light is actually working it's may be worth checking the correct bulb is fitted, that being H4 55/60W.

If it is, and you have a spare it's worth replacing, to see if this cures it, the system requires the correct bulbs to be fitted to work properly!

Martin

 

Update:

I know how annoying such vague questions can be, i'm just hoping some of these symptoms are signs of a common fault I can fix quickly.

After my last post in this thread I have been away from the car and unable to check Earth wires. I can't think where I would start with that...any suggestions for major/important Earths to check? Earths for the door-open warning light (near the door hinges)?

After driving the car for the last couple of days:

*The horn is now completely redundant. When I press it I can hear a clicking, like in a relay, down by my knee (while in the drivers seat).

*I've noticed none of the door check-lights come on if you open the doors while the car is running. Although if you open/close doors while the cars performing the check, you get a mess of messages from the check-lights.

*Upon starting the car on a couple of occasions, I noticed the fuel gauge needle was resting in the UP position (not DOWN like normal). After the car started it moved down to where the fuel level actually was.

*Maybe unrelated? There is a liquid very slowly speeping from behind where the fuel needle would be on a stalk. It looks oily, so i'm not sure how this would affect conductivity.

 

Marty, this is my third Sapphire, that's the only reason I knew that the fault lights were flashing in an unusual way...I didn't know what I described could mean an open circuit though! I didn't know about the specifics when it comes to the light bulbs either! I will check them later on today. Thanks alot.

CossieMoon, I have a RWD. Would this ecu-like-box you mention, be in a similar/same place?

 

They have two horns 1 either side they may hav packed up unlikely both at same time but if only 1 was working before then it cud be horns themselves! Check power to them and the click you can here is the relay in fuse box in engine compartment! Not sure where 2wd are but on a 4wd above the pass glove box there's a tray you need to pull that out and check that the multiplug behind is pushed in to the unit properly this may cure your door check problem! There's also a unit for your light check behind drivers side of bottom part of dash this may be ur problem for light on when head light is actually working and also check you have correct bulb fitted!

 

No on a 2wd you have your ecu and abs ecu in that place but it may be somewhere close it wudnt take much finding!

 

The aux warning system/graphic display has two ECU'S, there is one behind each "kick trim panel", the drivers side one is the "Bulb outage monitor".

Like I say this ISN'T a ECU problem, the problem lies with that circuit, so the first thing you want to be checking is the switch on the affected door!

This it NOT the 'Prong' switch by the hinges, that operates the interior lights, it is integral to the door latch and you can't see it without removing the door card.

Your problem is the horns themselves or the wiring I should think, the fact the relay clicks when the switch is actuates shows it to be working!

As said for the horn location, test each horn by wrapping a rag round it etc and applying 12V, if both work then you have a wiring problem.

Yes if you have condensation on the PCB this could cause the fuel gauge issue, in any case the gauge should always stay at the level when the ignition is switched off, and update when you first switch on after refuelling.

The cluster isn't that hard to remove if you wanted to inspect.

Martin

 

Just before i get to the replies...

I found this:



As you look at the fuses (stading at the front of the car), the burnt out one is far left and second row back. I thought the two there were spares, but I can't see how a spare fuse socket would heat up like that.

 

CossieMoon, I have found the ECU type thing. Well, I did on my wrecked car anyway. I've taken out both the ECU's that are wired to the Warning Lights/Fault display and have them put aside incase they are, or will be, of any use. I'll check the horns too, thanks!

Marty, that "prong" switch is what I assumed triggered the DoorOpen warning. Thanks for the info on where the real switch is. I will check all doors, as none seem to give a definitive or constant reaction on the fault display...more of a random or multiple door warning.

I've just noticed that the left rear warning light now comes on whenever I engage reverse.



I will keep posting updates as I check/solve things. Hopefully this will help someone else out in the future too.

 

You shouldn't have any spare fuses I don't think as they all do summit as they all have metal contacts below! That fuse is for cooling fans if I'm looking at picture rite! Its a common fault to melt you need to rerwire them before it catches fire! I take it you thought it was spare because on the fuse box cover its blank for that fuse isnit it? If so that's fans iirc!

 

Welcome to Cosworth ownership, I should of done my usual message, what you are seeing there is the cooling fan fuse, the wiring loom for which was sub standard when new!

You need to rewire the fans direct from the battery, you can buy looms to do so, NYRS and MSD to name a couple, the former also will supply you with a fan switch connector, if you don't want to DIY, if you do a search on here there are plenty of wiring diagrams!

It's also worth fitting an "uprated" switch, as the span of the OE one is the problem part, as the fans come on to early and stay on for to long, which is what leads to the fuse melting!

This and the fuel pump wiring are two chronic weak points on these cars, this suffers with a similar issue whereby the old wiring builds resistance and so the pump cannot draw the power it needs under load, i.e. when giving it a bootful, this can cause an engine meltdown! Again a loom to rewire direct from the battery is the remedy!

You want to get the fans sorted as at the moment they won't be working, unless someone has already rewired of course?

Also change the cam belt, unless you can be sure it has been done recently.

Martin