Having a long running battle with this saph i have newly acquired, and I need to get to the bottom of it!!!!
Some of you may have seen some other threads i have posted regarding this, but thought i'd start another one with all my findings etc... now i've got to a point where i don't really know what to do next...
So main probs are,

Fuel pump doesn't get power
Batt/Brake/Rpm/Oil lights, and fuel/collant guages on dash don't work, but the dash illumination, indicators and main beam lights work.

I have looked at various alleged wiring diagrams but they don't entirely seem to match what SHOULD be there as there seem to be subtle difference between the 3dr/esco/4x4 saph & RWD saph which i have.

So last night I havd another go at it with a multimeter, first thing i checked was the fuse No.22, this was reading 11.7V with ignition on, so that looked ok.
Then i checked the dash multiplug and here's where the fun starts.

Pin 1-Main Beam -Ok
Pin 2-Tacho/Oil light/Batt/Guages 2.37V
Pin 3-Oil light 2.37V
Pin 4-Indicators - OK
Pin 5-Tacho 9.35V
Pin 6-Temp. Guage 2.37V
Pin 7-Fuel guage 2.37V
Pin 8-Indicators -OK
Pin 9-Brake 0.89V
Pin 10-Batt light 2.37V
Pin 11-Dash illumination -Ok
Pin 12-Dash illumination -Ok

Also i attempted to measure at the fuel pump and it looks like there is only 0.5V there.

From looking at the diagrams i have, it appears that all of these are linked in some way, but the diargams are not entire accurate. So I'm hoping it's a common fault that will atleast fix 99% of this!!

 

if you unplug the multiplug from the back of the clocks, what voltage have you got on the black/yellow wire ?

if you unplug the plug from the fuel pump inertia switch in the boot, what voltage have you got there ?

 

I know the black and yellow wire your on about, can't remember which one that's for though, i think it's pin 2, there is no inertia switch, BUT the voltage is 0.5v with the ignition on.

 

The black/yellow should provide 12V for most of the things you've got that don't work.

There should be an inertia switch in the spare wheel well. If there isn't one there, have a look in the area of the driver's side kick panel - later injection looms have one there (shouldn't be there for your car unless a later loom has been fitted, or the car loom wasn't originally for a car with fuel injection). If you can't find one, then check the voltage to the fuel pump at the yellow relay on the passenger side behind the glove box, and at the connector for the engine loom to car loom (should be a black/red wire).

 

Cheers, yeah it did have an inertia switch but some idiot has gone crazy with the wiring (see my resto post ) and there are now just two bare wires poking into the spare wheel well with a really thin yellow wire scotch clipped to the back lights for a +ve feed to the pump! beggars belief really....

 

 

Not had a chance to have another look at this yet, hopefully i can get an hour in tonight.

 

Just realised another thing that's linked into this illusive wiring carry on, the check light system when you put the ignition on (doors etc...) that doesn't work either!

 

Probably hanging off the heated front window wiring.

 

Checked this last night, I have 0.5V at the connector behind the ECU and about the same at the relay, even though every other wire going in reads about 11.5v or higher... Also checked the black/yellow wire at the dash, that reads 2.3ish volts. All 4 wires onto the ignition read 11.7V or higher.

 

Is the relay currently fitted a standard yellow Ford one?

Sounds like you need to try another relay. They're nothing special, so try another with the same pin out - there are 2 pin layout types (but watch the relay's current rating).

Check that the fuel pump earth at the back of the car looks solid.

The black/yellow wire comes from fuse 22. Pull the fuse and measure the voltage that feeds the fuse. If 12V, replace fuse with new one.

 

Thanks, will do, I did check the voltage @ fuse 22 and it was 12v, fuse sees ok but i'll change it now you've mentioned it. I think the relay is a 12v 40 relay, it's the original ford one, will try and get another one to swap it with.
Thanks!

 

just had a quick read of your saph issues. it appears to have all the hallmarks of earth problems.
although there are lot of failures and poor voltage, try to sort out the simplest one first and it may lead to a better conclusion and the reasons for the rest.
i would look at the oil light first as its very simple. according to your measurements from the connector behind the dash you have 2.3 volts, but were did you earth the meter.i would sugest you earth the meter directly to the battery negative terminal to see if there is full continuity, or just earth the oil switch connecter direct to the battery neg terminal. if it lights or you get the 12 or so volts then you know where to start looking.

if there is 12v at fuse 22 and at b/y wire a the connector at the clocks then only an earth from the engine or the looms can cause the rest
see how you get on with the above and we can go through each system step by step, i have a full set of saph 2wd and 4wd wire diagrams and they have been very accurate and helpfull in the past to other members

 

Sorted!!!!!
Traced the problem to the fuse box, at fuse 22 (10amp) for the instruments the connector that connects fuse 21 & 22 (-ve)underneath the fusebox was dodgy, removed the wires from the box altogether and re soldered them back into the loom in another place with another in line 10 amp fuse, so theoretically it's the same as before but completely bypassing the original setup.

 

Nice one - my problem isn't dissimilar so will look there too

 

Cool, i replied to your thread, hope it helps you out, i spent ages trying to fix it but i got there in the end, just hope it's of some use to other people who may have a similar issue.
Let me know how you get on.