Looking for a lil help here. I'm having problems with my ac compressor popping the fuse. The other day I was driving home and my ac started blowing hot air. So first thing I did was check the fuse and it was good. Then I was looking at the connection from the compressor to the wire harness and noticed that one of the wires was broken. So I took the connector apart and re soldered the wire back on to the connector and put it back together. Now the fuse keeps popping and clutch never engages before the fuse pops. Could I have a relay issue or is the compressor no good? Please help!! Thanks in advance!!

 

Measure the resistance through the field coil. If the resistance is a few ohms, that's probably not the issue. If it's nearly zero ohms, the field coil is probably shorted. While you have the connector disconnected, measure the resistance from each of the wires to ground and make sure they are not both shorted to ground. If so, one of them should not be. Which color wire was broken? The black wire is ground and the dark blue/yellow wires is the power from the fuse. My caveat here is I'm using a diagram for the 2014 and assuming 2016 is the same.

Also, what amperage was the fuse that blew? Did you confirm the correct amperage (10A) fuse was installed? Did the wire look like it broke from fatigue, hear, or was it cut?

The relay would not be the cause of the fuse blowing when the A/C compressor is commanded on since the 10A fuse (Fuse 62) is after the relay. The fuse only has power when the relay is closed.

-Rod

 

[QUOTE=SHO Rod;3393673]Measure the resistance through the field coil. If the resistance is a few ohms, that's probably not the issue. If it's nearly zero ohms, the field coil is probably shorted. While you have the connector disconnected, measure the resistance from each of the wires to ground and make sure they are not both shorted to ground. If so, one of them should not be. Which color wire was broken? The black wire is ground and the dark blue/yellow wires is the power from the fuse. My caveat here is I'm using a diagram for the 2014 and assuming 2016 is the same.

Also, what amperage was the fuse that blew? Did you confirm the correct amperage (10A) fuse was installed? Did the wire look like it broke from fatigue, hear, or was it cut?

The relay would not be the cause of the fuse blowing when the A/C compressor is commanded on since the 10A fuse (Fuse 62) is after the relay. The fuse only has power when the relay is closed.

It was the blue and yellow wire that appeared like it was hit with a rock or something from the road. And yes I did confirm that the correct fuse was replaced with a 10A fuse (F62) I will do some checking today with the info you gave me to see if the coil is shorting out. If it is the coil, can I replace it or is it built in to the compressor?

 

I re-read your original post and since you mention the fuse was good before the broken wire was fixed, it would be a very big coincidence that the field coil would short at the same time or just after the wire broke. So the first thing to check would be the repair to make sure there is not a strand or something that is touching the adjacent wire. Also make sure the connector isn't damaged and allowing the two terminals to short inside the connector body. A continuity tester should read open / OL if you check for continuity between the two wires for the field coil at the wire connector end. If there's no short measured, another thing you could try is to leave the connector free of the field coil, install a good fuse for F62, then start the truck and turn on the A/C. If the fuse again blows, there is an issue on the wiring end. If the fuse does not blow, then you're again looking at the field coil. The field coil is connected to the A/C compressor, but can be replaced without replacing the entire compressor. It does require removing the serpentine belt, removing probably a 10mm nut, and likely removing a snap ring.

-Rod

 

Rod, first of all thank you for your time and help! It is much appreciated. I checked my work on the connection that I did in the connector and is good. I put a fuse in with it disconnected from the compressor and it did not pop the fuse. I checked the continuity of the compressor and is only reading .1 ohms. So my guess is the coil is shorted out. I am going to get a new one on order and replace it this weekend. Hopefully this solves the issue.

 

Well I replaced the clutch coil and it is still popping the f62 fuse. I'm at a wall here.. lol is there anything else I can try before I go out this in the shop?

 

Did you happen to measure the resistance of the new field coil? If the fuse only pops with the coil connected, the issue almost has to be the coil.... You might try to perform a diode test on the wiring at the coil connector with the coil disconnected to make sure the diode is working properly, although if the diode were the issue I'd expect that to cause a problem when the A/C clutch disengages versus engaging.

Are you sure the correct size fuse is installed? With your former coil measuring 0.1 ohms DC, that would equate to a surge current draw of 138 amps (assuming a system voltage of 13.8 volts). Now there will be some inductance associated with the coil that will have an effect on the dynamic resistance, but rough numbers I'd expect the field coil should have something more like 1 ohm DC resistance or more.

EDIT: The Internet seems to be consistent that the coil should measure between 2 and 5 ohms when tested using a DMM.

-Rod