This morning I went out to move the Trooper to a level spot so I could adjust the clutch cable. Started her up and noticed that the fan was not working and gas, battery and brake idiot lights remained on instead of going out after start up. Everything else worked, wipers, lights, radio, cig lighter, gas gauge, oil pressure, etc. I also noticed that the rear refroster switch has no power either. Everything was working fine yesterday. I checked all the fuses in the engine compartment and they were all good. I have read all the posts about the blower motor, and they all lean towards a relay. I am leaning more towards a fuse. Are there any "hidden" fuses up under the dash? What would cause the idiot lights to remain on, and no power to the rear defroster switch? <img src="/forums/images/graemlins/confused.gif" alt="" /> Any ideas, suggestions, advice? 1987 Trooper, 2.3 5 speed.

If the idiot lights are on, there is a really good chance that your alternator has decided to depart for car parts heaven. The fact that the heavy current users, which are mostly, if not all controlled by relays, are not working is another sign.

Wouldn't the alternator make the obligatory high pitch screeching sound like the bearing going out or something? It is not hard to remove. Maybe I will take it down to schucks and have it tested. If it is not the alternator, what else should I check for?

Sometimes the electrics fail without the bearings failing... the christmas-tree display of most every light in your cluster is CLASSIC Isuzu alternator failure. Definitely swing by a Shucks or some other parts store and have them check it out -- most will do a free underhood electric systems check.

Randii

So that would cause the blower and the rear window defroster not to work, because they won't work on battery power, but everything else will? But wouldn't that also cause the motor to run poorly, since doesn't the alternator supply power to the electronic ignition as well?

On Isuzus the PCM monitors the alternator output. If there is a problem it will cut out all "non essential" equipment. The blower, rear defroster, etc. are considered non essential. That way it will allow as much power as possible to try and get you to where it can be fixed.

Yup, been there before. My Rodeo would start and remain running, but no blower fan and battery light on the dash. I think the shop that tested my alternator said bad L termanial. After replacing the alternator, everything returned to normal.

I agree, definitely sounds like an alternator to me.

-Rob