I have a '96 B3000 V6 with no check engine light. Checked the bulb in the instrument cluster and it was good. I tried to check for continuity from the instrument cluster to the PCM. One of the leads from the bulb (connector 1, pin 13) seems to make it to the PCM harness . The other lead (connector 3, pin 9) goes nowhere well at least no where I know to probe. But then again I don't know where it should go! Could it have a bad ground? Or could it be a bad PCM? I also checked the fuses and they all seemed to be good. Any body have a decent wiring diagram. My Haynes manual is worthless in this department. No other problems of note. I'm thinking I might have to hotwire the CEL it to the ABS light so I can 'pass' inspection.

Thanks,
Dave

 

One side of the bulb should go to ground. check between a good ground and the bulb. No more then 1-2 ohms is all you should see. The other will have 12 volts if the light is on. You should be able to see one side or the other is bad.
Sorry I can't be more help but I don't have any diagrams for that year.
Dave

 

That looks like the problem. I have 12 V on one side and an open circuit on the other. Next question: What gauge wire should I use to patch it?

 

I have a book on a 98 ranger (it may well be different then yous) and it shows +12v on one side and the ground is provided to the light by the PCM. So either the Pcm is not giving you the ground (no fault) or the wire is open between the PCM connector and the light bulb. Putting a ground on the bulb will turn on the bulb, but it will never go off. I would never recomend hooking it to the ABS light. Check to see if you are getting a ground out of the pcm when running and an open to ground when not running key off.

Someone will be by and have a wiring diagram and you can get the PCM pin number for the CEL.
Dave

 

On the '96 Ranger 3.0L, Pin # 2 (PK/LG) on the PCM connector is for Malfunction Indicator Lamp (MIL) Control

 

I'm still having trouble. Pin #2 on the pcm gives 30 ohms to ground with the key on/engine off and open circuit to ground with the key off. Pin #2 is open circuit to both sides of the CEL bulb.

Does this mean A) bad pcm B) bad wire between pcm and cluster? I am going to try running a jumper between pin #2 and the cluster to see if that works. The 30 ohms to ground seems a bit high. Shouldn't that be more like 1-2 ohms?

Thanks for your help.

 

If you put a ground on the wire going to pin 2 on the pcm the light should go on. That would prove out the light circuit. The other side of the bulb should have 12v on it when key on.
Dave

 

I think its ok now. I ran a jumper between the cluster and pin 2 and turned the key on and I got it to light! I then started the engine and it turned off like it is supposed to. I guess the wire between #2 and the bulb was bad. I just ran a new wire between the cluster and pin #2. Finding a route through the firewall was tricky...

After putting every thing back together, I restarted the engine to check my work and the engine light comes on and stays on. Grrrrrrrrr! I pull the battery cable, wait and restart, the light goes off like it is supposed to. Stop the engine, restart, light comes on. I am guessing that I have a code that is screwing things up and that the engine light is right. During all this fiddling I replaced a the cannister purge solenoid assembly which had set a code during my inspection. In a normal situation, should the engine light go off by itself after the PCM has relearned everything after having its brains erased? Or does the engine light indicate something else is wrong now?

I curse electrical wiring.....

 

Scan for codes to see what might be setting the CEL. It's possible that somebody cut the wire between the PCM and instrument cluster, so the CEL wouldn't be on....

 

I'm taking to the local parts store tomorrow to get the codes read. I bought the vehicle new in 1996 and I didn't cut it. When I took it in for inspection it had a 1443 code so I replaced the purge assembly so in theory that should be OK now. I've never seen the CEL until today when I hotwired it. It just seems to be bad wiring from the factory. I never noticed because after all, if you don't miss something you don't know you have! I'll keep in touch.

Thanks.

 

Just to let you all know... I went to Autozone and had them pull the codes. It had a P0340 for the camshaft pos. sensor. I replaced the sensor and the engine light now stays off when it is supposed to and comes on when it is supposed to. Looks like I have fixed everything! This is a great site and because of the info here and the intelligent and helpful people I saved mucho dollars! I owe y'all a debit of gratitude and a virtual 6-pack. Thanks.

 

Glad to hear its better now.

 

Good for you !
Dave