my CEL doe not illuminate and i need to figure out which wire feeds it so i can determine whats wrong. i do not even know what the light looks like what is the symbol for check engine on these trucks? is it a wrench. a motor, a CEL ?
i bought this truck and didnt notice the light was not working, why would i . if the light was on, i sure would have noticed it. ,

 

Now would be a good idea to open the owner's manual to learn what all those things on your cluster mean and where they are located.

There is no "wire" that feeds the bulb, it's all driven by circuitry inside the cluster's electronics.

It might be a burned out bulb or, if the seller or previous owner was unscrupulous, the bulb may have been removed to conceal a fault.

 

if i had a manual, that would have been the 1st place i started but nope, no manual in this heap.

"There is no "wire" that feeds the bulb, it's all driven by circuitry inside the cluster's electronics."
the CEL has to be powered by something, it doesnt work by wishing it to be on. (sarcasm intended)

the cluster does not have bulbs for the idiot lights, it uses LED's, which are soldered into the circuit board. so it couldnt have been removed, this was the ist thing i suspected and visual inspection found LEDs
the "circuit is fed by????? yup, you guessed it, WIRE. so, as i asked previously, i am looking for a wiring diagram/schematic for the dash cluster to determine which WIRE feeds the cluster circuit board for the CEL .

 

Read my signature, get one. the cluster does not have bulbs for the idiot lights, it uses LED's, which You should have stated that, then I wouldn't have wasted my time.

Ford does not release the schematics of the instrument cluster module.

 

There is a 2-wire data line that runs from the ECM computer to the microprocessor built into the instrument cluster. The ECM communicate with the IC over this data line. If the CEL needs to be on the ECM tells the IC microprocessor to do it. That's why there is no single wire that runs from the wiring harness to the IC to turn the CEL on, it's all done internally within the IC.

 

I have inputs to dash cluster on another computer but no internals , So if its a broken circuit board etc, it won't help. Not that you should not check each terminal for the right stuff . But the can bus gives it its info I believe.Once you test each input I'm afraid you need to send it for repair or get a rebuilt one ,they are bad about poor solder joints I hear .Of cousres on power up it should light cel without a fault . Don't know if that's a chip fault or what .
I will go to location with limited drawings soon .

 

so, just to close out this thread, i found my problem, i dismantled my dash cluster completely, which required pulling the needles off of all the gauges ( a very stressful operation because with every creek and crack, you think the whole gauge is going to pull off ) anyways, when i pulled the face off of the circuit board, i found 3 tiny pieces of tape, one over the CEL, one over the ABS light & 1 over the TPM light. so, someone in this vehicles past pulled a fast one. and they must have really twanted this light out because again, taking this dash board cluster apart is no easy process.
just thought i'd share my findings

 

I loath hack work!

 

It can always help someone . I can see someone killing the seatbelt alarm but this is ridiculous.

 

According to my owner's manual I can disable the seatbelt ding, at least down to just a few seconds of it. That's for a 2001 Navigator, I don't know if that ability has been removed since then.