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98 HVAC Fuse Blowing Trouble


Tirpitz
08-29-2006, 08:23 PM
Ok folks, sorry if this has been asked and answered before. Forgive me. I have a 98 Chevy ZR2 Blazer 2 door 4WD 4.3 liter vortec. My problem is when I turn on the dash switch to get ac, heat, max ac, defrost...ect. my number 9 slot fuse blows. It is a 20 amp fuse or 20. Anybody have any ideas? Thanks for any help and sorry if this has been posted and answered before.

BlazerLT
08-30-2006, 05:50 PM
What is that fuse for?

Tirpitz
08-30-2006, 06:29 PM
It is for the HVAC. The slot is number 9 on the fuse panel inside the vehicle. It is a 20 amp fuse. It's funny cause I can get the vents to work if I have the setting on top setting or floor board setting. If I put it to off and try to turn it on it blows fuses in the max ac postion, ac postion top and bottom postion, floor board and defrost postion and defrost setting. I'm wondering if it's the dashboard console switch.

BlazerLT
08-30-2006, 08:32 PM
More than likely you have a dead short in your blower motor.

Tirpitz
08-30-2006, 09:55 PM
I thought the blower motor was bad also. So I went out and bought a new blower fan/moter. Before I cut out the old one I diconected it and pluged in the new one and it still blew the fuse. I'll try it again though. Any other ideas?

BlazerLT
08-30-2006, 10:13 PM
Has to be something behind the dash in the wiring or the wiring going to the blower motor.

blazee
08-30-2006, 10:25 PM
There's a schematic in this thread that might help you find the problem:
http://www.automotiveforums.com/vbulletin/showthread.php?t=503195

Lith1um
09-05-2006, 11:50 AM
Ok folks, sorry if this has been asked and answered before. Forgive me. I have a 98 Chevy ZR2 Blazer 2 door 4WD 4.3 liter vortec. My problem is when I turn on the dash switch to get ac, heat, max ac, defrost...ect. my number 9 slot fuse blows. It is a 20 amp fuse or 20. Anybody have any ideas? Thanks for any help and sorry if this has been posted and answered before.

Just a guess,

It could be the ac compressor clutch has a short.

Pull the electrical plug off of your ac compressors clutch.

Does it still blow the fuse without the clutch in the loop?

Tirpitz
09-05-2006, 02:10 PM
Well here is the latest. I replaced the AC compressor less then a year ago. This past weekend I replaced AC hoses & Accumulator. Added oil to system. Turned the vehicle on all ac settings worked at all fan speeds and no blowing fuses. Even defrost setting worked without blowing fuses. I then hooked up a vaccum to vaccum the system and check for leaks. Then started up the vehicle put the ac on max to charge it with freon and the fuse blew. I'll try disconecting the compressor from the loop tonight and see if it is a bad compressor clutch. I hope not cause the thing is almost brand new with hardly any use on it cause of the fuse blowing problem.

jfgent
08-08-2008, 11:03 AM
Anyone know the final fix to this problem. I have a 2000 S10 pickup with a 4.3L V6 that is blowing the same 20 amp hvac fuse. I have disconnected the blower motor, resistor pack and AC compressor and still get the same result.
I have measured the wires from the resistor pack plug to ground and found a dead short from the dark brown wire to ground. I thought I would just eliminate this as the cause by cutting this wire at the resistor pack plug and at the other end where it plugs into the fan speed switch. Fuse still blew after this. There appears to be something else in the circuit between the fan select switch and the resistor pack. I can not find a wiring diagram for this circuit and have no idea what might be there. Anyone with any ideas?

ZL1power69
08-08-2008, 10:23 PM
Anyone know the final fix to this problem. I have a 2000 S10 pickup with a 4.3L V6 that is blowing the same 20 amp hvac fuse. I have disconnected the blower motor, resistor pack and AC compressor and still get the same result.
I have measured the wires from the resistor pack plug to ground and found a dead short from the dark brown wire to ground. I thought I would just eliminate this as the cause by cutting this wire at the resistor pack plug and at the other end where it plugs into the fan speed switch. Fuse still blew after this. There appears to be something else in the circuit between the fan select switch and the resistor pack. I can not find a wiring diagram for this circuit and have no idea what might be there. Anyone with any ideas?
Welcome to the site. This thread is almost 2 years old. Best to create a new thread in the problem diagnosis section with a link to this one.

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