A.c. Relay keeps blowing...

[FordGirl85]

I have a 05' Ford explorer XLT 4.6L v8 4x4. It ran hot one day so we replaced the thermostat and a coil pack and started the truck and for some reason my a.c wouldn't blow cold anymore. It was working perfectly fine 30 mins before! Finally figured out the relay was blown so put a new relay in and it blew tht one too. Idk why it keeps blowing the relay? Also now it's throwing a code for primary/secondary circuit malfunction ignition coil G..??

 

[Fix4Dirt]

I have a 05' Ford explorer XLT 4.6L v8 4x4. It ran hot one day so we replaced the thermostat and a coil pack and started the truck and for some reason my a.c wouldn't blow cold anymore. It was working perfectly fine 30 mins before! Finally figured out the relay was blown so put a new relay in and it blew tht one too. Idk why it keeps blowing the relay? Also now it's throwing a code for primary/secondary circuit malfunction ignition coil G..??

coil grounded right?

 

[J_C]

Welcome to the forum!

I'd unplug the compressor clutch and if it no longer blows relays, replace the clutch. EDIT1: See below first, I thought of another possibility.

However it seems strange to me to be burning up relays rather than blowing the fuse.

When you put the new relay in, did it work for a while and then stop? What is the evidence that the relays are blowing? EDIT2: If they are really going bad, my #1 (and only at the moment) suspect would be that your relay box contacts are corroded and this is causing excessive resistance, causing heat.

I'd look over the spark plug wires in case they're on the wrong coils, and consider swapping the old coil pack back on as a test, if it wasn't throwing the code before the swap. What is the code # it shows? I'd also examine the coil pack wiring for breaks or shorts, and the condition of the coil pack connector contacts.

 

[Mbrooks420]

I’d check all wiring in the area. It’s possible you disturbed some brittle wiring.

 

[J_C]

FordGirl85, in case you had already ready my last post, I've edited it to include another possible reason why the relays might fail, relay box contact corrosion (or frayed wires' resistance) causing heat.

 

[Dean peulen]

Read this problem on this forum ,a cable under the car near the oil filter plastic splash guard,rubs on the guard and wears through the cable causing blown AC fuses . This problem was then check by many of this post readers and lots had same worn through wire insulation or broken wire because of this rubbing cable. Varying fixes from electrical tape to new cable and bending a cable bracket to stop future rubbing.