A/C Fuse Keeps Blowing
A/C Fuse Keeps Blowing
The 15A fuse (#5) that the A/C is on keeps blowing in my 1997 F-150 (4.2L V6 / 5spd M/T).
I had the cruise control recall done on this truck, and I noticed this issue occurring some time later. I am not sure if it is related but I mention it because the cruise control is on the same fuse.
I have been ignoring this issue for a while but I'd really like to have my A/C back. I bought a pack of 15A fuses yesterday and installed one to test.
I drove a few miles, occasionally using cruise control, and the fuse did not blow.
Then, I got on the highway and turned on the A/C and cruise control. A/C blew cold. The fuse blew after approximately 3 miles (I could tell because the cruise control stopped functioning).
According to what I've found so far, the following items are on the fuse:
Backup lights via transmission-mounted switch
DRL (if equipped)
Cruise module (operating power)
Blend door actuator
HVAC function switch (feeds A/C clutch circuit)
I'm not too well-versed in troubleshooting (I change my oil but don't do much beyond that), so I could use some help. I have a multimeter and basic electrical knowledge but I could definitely use some advice in how to track down/repair this issue.
I had the cruise control recall done on this truck, and I noticed this issue occurring some time later. I am not sure if it is related but I mention it because the cruise control is on the same fuse.
I have been ignoring this issue for a while but I'd really like to have my A/C back. I bought a pack of 15A fuses yesterday and installed one to test.
I drove a few miles, occasionally using cruise control, and the fuse did not blow.
Then, I got on the highway and turned on the A/C and cruise control. A/C blew cold. The fuse blew after approximately 3 miles (I could tell because the cruise control stopped functioning).
According to what I've found so far, the following items are on the fuse:
Backup lights via transmission-mounted switch
DRL (if equipped)
Cruise module (operating power)
Blend door actuator
HVAC function switch (feeds A/C clutch circuit)
I'm not too well-versed in troubleshooting (I change my oil but don't do much beyond that), so I could use some help. I have a multimeter and basic electrical knowledge but I could definitely use some advice in how to track down/repair this issue.
I tried this (along with unhooking the master cylinder brake pressure sensor), thanks.
I also tried removing the (aftermarket, questionably installed by previous owner) trailer brake controller wiring.
Both approaches netted me about 10 minutes of nice, cold A/C before the fuse went.
Now I'm thinking it's probably something with the A/C itself.
What I'm also wondering -- the broken blend door problem that is so common on these trucks -- could a failure here somehow lead to a blown fuse? The actuator is on the same fuse.
I also tried removing the (aftermarket, questionably installed by previous owner) trailer brake controller wiring.
Both approaches netted me about 10 minutes of nice, cold A/C before the fuse went.
Now I'm thinking it's probably something with the A/C itself.
What I'm also wondering -- the broken blend door problem that is so common on these trucks -- could a failure here somehow lead to a blown fuse? The actuator is on the same fuse.
I know this is an old post but I am having the exact same problem except my fuse blows as soon as I turn my key. I have traced the harness and there is no sign of a word wire or a wire grounding out. Did you figure out what the problem was?
It helps if you include specifics like which vehicle you have.



