I just swapped out my stock gauge cluster w/out tach with a new one with a tach, I also swapped the speedos so I would keep my current milage, the swap was a breeze everything plugged right in and all the gauge work and function just fine. Except the "Check Engine Light" is now on and won't go off, the "CEL" is/was in perfect order prior to the swap with the stock gauge cluster. I reset the PCM multiple times to no help, I'm a little stumped since everyhting is functioning just fine.

I know you did the same swap, just curious if you also experienced this or if you might have an idea to the problem.

Thanks

BTW- I'll have the cluster out later today to replace the bulbs so I'll slip my old cluster back in there and see if that CEL is still on.

 

I'm clueless. If everything is connected and works the CEL shouldn't re-at. Pull the codes?

 

Houston we have a problem!

Well with this new cluster I noticed my battery amp gauge was sitting noticable lower this morning, I figured it was just the gauge and not to worry about it since the gauges aren't accurate at all, well on my drive home from work my power inverter started beeping(it's what used to power my playstation2) well the only time it is supposed to start beeping is when the battery is getting low, (like if you're playing PS2 with the engine off it will let you know the battery is getting low and you should turn the truck on so the amp can keep constant power to the battery so you're not left stranded)

So when I hear the beeping while I'm driving I turn off my stereo..that helped stop the beeping for a few miles then it came back so I know my amp wasn't charging the battery and I've been just running off of the battery since the install of the gauge cluster....which now explains why I had the check engine light.

Limped home, truck was sputtering up my street, popped out the new gauge cluster w/tach and popped in my old one and all is fine, no check engine light, battery gauge is back to where it was

Well it was nice to have a tach for one day

So this new gauge cluster wasn't letting my amp charge causing the "CEL"

 

There's an on-board voltage reguator, sounds like it could be kaput. I don't know if the I/P boards are servicable or not. Anything can be fixed, the trick is findding someone who knows how and is willing to do the work. Check the yellow pages under "automobile, electrical" and "speedometer" maybe you'll turn up something.

 

Guess I've got a winter project lol
thanks for your input

 

Purdy sure I found the problem...burnt out dashlight bulbs...how stupid

I forgot they complete the ciruit.

 

I don't think so. A burned out bulb gives you an open circuit. Your problem is something creating a closed circuit that leaks current. that cannot be a burned-out light bulb. Again, my first guess would be the voltage regulator on the instrument cluster itself, but there could be several other components that could have failed in a way that would cause leakage.

 

I'm with the Ranger man on this one. I know that in Mustangs, there is a regulator in the instrument cluster that is necessary for the charging system to work. I can't explain the exact science of it, but the common problem is guys who drive their Mustangs while the cluster is out, for whatever reason. They end up with a dead battery, and don't understand why. On the '64 Ranchero, the regulator was right there on the back of the cluster, and was simple to replace. Things have changed a bit in the 32 years between the time it and your truck were built, and I'm afraid I don't know how to replace yours. I'd do exactly what S/R suggested.