93-12Smoke

Ok so tonight on the way home my CEL light came on when I first cranked the truck. Turned the truck off and back on and the cel was gone. A little farther down the road I stopped and turned the truck off. When I cranked it back the CEL was on again. Killed the truck and restarted it and the CEL was gone. Every time the gauges showed everything was good. Stopped again for fuel and when I cranked the truck the CEL was on again and for good and the voltage gauge was reading low also the a/c was till blowing cold so I knew it was not the CPS. I checked the codes and got 12, 33 and 41.

12- Battery Connection Disturbed
33-A/C clutch relay shorted or open
41-Generator Field not switching properly

On the way home the volt gauge was reading about where it normally does until I slowed down to city street speeds and then it fell back down low.

Checked the alternator using my handy dandy battery charger and it showed the alt was putting out 0%. The manual says that doesn't mean its not putting anything out but that its not enough to make a difference in the state of the battery.

I swapped the a/c relay and the asd relay and still had a CEL, (yes I had reset it by disconnecting the battery). Now I have CEL #12 and #41, no more #33.

What gives? The alt relay was appears to have been good as it cleared the a/c code but the a/c relay appears bad since it did not clear the alt code.

But if that is correct why was the a/c still blowing cold if the a/c relay is bad?

Any ideas or help would be appreciated. Planning to try to pick up new relays tomorrow and take the alt to the part store for testing on their machine.

93-12Smoke

I i also have a 4th relay not pictured in the stickey. It's taped into the wiring harness near the others. Has a black wire, green with white tracer, green wire and a black with orange tracer. Anyone know what it does? Same part number as the others.

j_martin

Intermittents........Usually connectors.

Also, when the alternator nears end of life, the short brushes and dirty slip rings will make em intermittent.

The PCM sees the fault and sets the code, but it's gone when you're looking.

Fun, eh.

j_martin

Hey 93, you will get better answers if you keep it to one thread.

With a test light, engine running. One terminal on the alternator should be bright, the other blinking. If it's out, the alternator is bad. If both are out, or both are bright, it's connections, relays, etc.

93-12Smoke

Yeah, i started a thread with a searchable title. No power on bottom of the two small studs. Links check out good.

maybe368

posted in wrong thread...

93-12Smoke

Had parts store test the alt. Tested bad on their machine. New alt fixed the problem. Guessing the A/C code was a fluke or somehow related to the alt failing but it's code cleared too. The a/c was working despite the code.

j_martin

That didn't take long once we got all the info together in one spot.

93-12Smoke

Yeah, I was trying to make sure and rule out the other electrical problems before throwing parts at it.

This forum definitely helps save money every now and then. Usually it makes me spend more!!!!!

thrashingcows

Glad you got things figured out and fixed. But I have to as what "CEL" means....never come across that one here on the board.

93-12Smoke

Check Engine Light

thrashingcows

Ahhh...makes sense now....Can't believe I couldn't figure that one out myself...

BILTIT

Don't feel bad, took me a while too.

j_martin

93-12Smoke

You never really see post about check engine lights.