Dying Alternator?

[kimcrwbr1]

Being erratic tells me it is a loose/bad connection somewhere possibly near where you hooked the alarm system up. Use a small screwdriver or ice pick to push all the pins in fully on all connectors after you clean them with electrical cleaner.

 

[stsalvage]

I'd sure be checking it's output after that. Running with a stone dead battery can fry all sorts of things and puts an awful load on the alternator and it's wiring.

Heard a story from my shop foreman once, he gave a guy a jump from a stone dead battery, told the guy to get a new one before he fried the alternator. The guy told him it'd be ok, he'd just drive around a bit to charge the battery up. 15 minutes later Bob passed the truck on the side of the road, engine bay in flames.

I saw the recall on these trucks for the 1989-92 trucks about the internal plug that connects to the alternator it seems like it can get a ark and catch on fire.

Here is another one you need to let guys know about its the cruise control switch on the brake master clendyer Funny thing about that switch its always HOT 12 volts after you turn the Key off It cost ford over 15 million in Law suits it burn down 29 houses killed 13 pealpe.Ford denied it was that.Until you go on YOU TUBE guys at a Fire station had one light up in front of there camera crew shows how water and brake fluid and 12 volts DON"T MIX