1996 ford explorer XLT PCM problems

[jamesexp]

hey guys i recently bought a 1996 ford explorer that wont pass emissions due to no check engine light in key on position or while running. it is popping code p0153 witch i fixed by putting new o2 sensor in, but still no check engine light i was told by a "mechanic" on justanswer.com that is was a bad pcm can anyone help me verify that? can i replace it with a used one? please help

 

[koda2000]

if the CEL doesn't come on during the "bulb check" (key ON engine off) the bulb is burnt out. real PITA to replace it.

 

[jamesexp]

i have taken dash out and changed bulb also i got a used cluster because i thought maybe cluster was bad and still no CEL.

 

[budwich]

well there is more to troubleshooting than just replacing parts. get a meter and check the wiring coming into the cluster to see if the ground is being sent to light the bulb... of course, then you can also check the same at the PCM... then you will likely have your answer.

 

[jamesexp]

Ok guys I removed the cluster and checked for power on my cel contacts and nothing so I followed the ribbon to the connector and checked those spots, come to realize the power wire (red with yellow stripe) is there but there is no wire to the left of it for the ground can any one tell me if this plug is supposed to be missing the wire next to the red with yellow stripe hot? Or if its supposed to be there what color is it so I can trace it from the pcm or where ever it might come from. All the help is greatly appreciated from everyone

 

[jamesexp]

Ok guys I removed the cluster and checked for power on my cel contacts and nothing so I followed the ribbon to the connector and checked those spots, come to realize the power wire (red with yellow stripe) is there but there is no wire to the left of it for the ground can any one tell me if this plug is supposed to be missing the wire next to the red with yellow stripe hot? Or if its supposed to be there what color is it so I can trace it from the pcm or where ever it might come from. All the help is greatly appreciated from everyone

 

[budwich]

PNK/LT GRN on pin 9. Further did you check to ensure that voltage was at the socket? not all pins / wires are present in the connectors... further is the cluster the original, has it been replaced. Some people have swapped things and find their cel shows up elsewhere like the fuel cap light...

 

[NICE59FORDF100]

Are all the other gauges working? The CEL gets power from fuse 11 (7.5 amp) in the dash fuse box. If no power is on the circuit, then the pcm can ground out the bulb all it wants, but the bulb will not illuminate. Also shared on that circuit is the voltmeter, oil pressure, tach, etc.

 

[jamesexp]

I should have the red with yellow stripe (hot) and the pink with light green stripe (ground) on the same connector right? I can see it coming from pcm and where it comes in behind my cluster but it goes to a different connector a white one. I made a jump wire from pink with green stripe and it made check engine light come on but stays until vehicle is started then it shuts off. It should only stay on for 2 seconds during key on engine off test right? And then if I have engine codes be on while engine is running right?

 

[jamesexp]

Are all the other gauges working? The CEL gets power from fuse 11 (7.5 amp) in the dash fuse box. If no power is on the circuit, then the pcm can ground out the bulb all it wants, but the bulb will not illuminate. Also shared on that circuit is the voltmeter, oil pressure, tach, etc.

Yeah I tried that I have power but no ground but I definitely appreciate the suggestion

 

[budwich]

I should have the red with yellow stripe (hot) and the pink with light green stripe (ground) on the same connector right? I can see it coming from pcm and where it comes in behind my cluster but it goes to a different connector a white one. I made a jump wire from pink with green stripe and it made check engine light come on but stays until vehicle is started then it shuts off. It should only stay on for 2 seconds during key on engine off test right? And then if I have engine codes be on while engine is running right?

That's what is supposed to do unless you have "warnable codes" stored. Anyways, as I indicated, some "persons" have changed their cluster for various reasons (some of which might be mileage related... ))) ) and as a result the cluster may not be matched with the actual vehicle. As you have found there is a "correct" wire showing up somewhere. Your "fix" is OK. Now that you know the incoming wire / connector, you can trace that wire thru the cluster board to see which bulb it was actual trying to light... my guess it is the fuel alert bulb... but may be not. When you turn your key to just on and leave it there, what if any lights stay on... if there is one, that's where your wire was heading.

 

[jamesexp]

Funny you say that cause I removed my jumper wire and all the lights and was tracing the ribbon and now I put everything back together my fuel reset light stays on I'm at wits end with it I need the light to work properly so I can go thru emissions

 

[budwich]

so... doing your "wiring trick" is fine, I believe, in most states, they only worry about the actual CEL light... other lights on are not a concern. Further, just remove the fuel reset bulb once you have done your "wiring trick" and you are good to go... assuming you don't have any codes which appears to be not the case (ie. you have a code, hence the light)... my guess when you took out all the bulbs, the fuel reset one was burnt... once you put them randomly back, you put a good one back and now have the light...

 

[jamesexp]

Thank you for all I appreciate all you help I'm gonna try to go thru emissions tomorrow and I'll let you know how everything works out