olnick
Full Access Member
- Joined
- Feb 7, 2019
- Posts
- 62
- Reaction score
- 42
- Location
- Milford NH
- First Name
- Nick
- Truck Year
- 1978
- Truck Model
- c15
- Engine Size
- 1982 350 4 bolt mains
Around town in 80 deg humid conditions had the A/C on blowing nice and cold!! stopped at parts store went to leave NO A/C/heat or any blower speeds. Got home 2 mile ride went and got my DMM to check for power. top of heater fuse was good and the bottom connection when touched with the meter lead gave out a small spark and all was well! A/C worked well for another week then went out again, same check same results! this time I removed the fuse (25 AMP) and cleaned the fuse block contact locations. replaced the fuse and A/C was back!! Made a delivery to Sons house 100 miles away (in the POURING RAIN) all was well going there! A/C defrost was working fine. Unloaded the truck went to leave and again NO A/C heat blower. About 20 miles on the way back enough air had finally blown in at highway speed to keep the windshield clear (STILL POURING OUT) Got home and let it sit got the wiring diagram out and did a quick trace of the heater / A/C circuit. it couldn't be any simpler!! next day My DMM tells me the same thing power at top of fuse nothing at bottom this time no spark when checking the contact. I pulled the fuse and check to make sure the fuse is testing good. (I can see the fuse is NOT blown through the glass tube) it tests OPEN! I then twisted it and it fell apart with the lower end being burnt off of the end cap! replaced with new 25 AMP fuse allis well.............
