HVAC Woes, fan not working, temp not working . . .
06-11-2012, 01:34 AM
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HVAC Woes, fan not working, temp not working . . .
Basically, it's all messed up. The fan was working for a while but now has died completely. Once in a blue moon when I start the car it spins up (I keep the controls on full cold, econ selector, fan speed medium) - but the kind breeze doesn't last for more than a minute or two. I'm in full diagnosis mode and this is what I've found: 1.) Fan will work in defrost setting (full speed), 2.) with defrost relay removed, fan is still inop. So, questions: 1.) what's the next step to determine what's not working? 2.)is there a work around to get me some vent fan, it's getting hotter these days! TIA
06-11-2012, 10:22 AM
#3
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The fan can be powered thru two different paths.
Fuse #17 to blower relay (Relay XXI) to blower switch to resistor pack to fan.
Fuse #17 to defroster relay (Relay XXII) to fan.
In almost every case:
- If the fan does not work at all, it is usually Fuse #17, its connections, the blower motor or its connections.
- If the fan does not work on any low speed, but works on 4 (highest speed), it is usually a broken wire in the resistor pack, or a connection in that circuit.
- If the fan does not work on any speed setting, but works on DEFROST, the problem is usually a faulty blower relay (Relay XXI)
- If the fan does not work on DEFROST, but works on other settings, the problem is usually a faulty defrost relay (Relay XXII).
If you go to our website, and drill down thru the tips and links to Wally's World, then HVAC, you will find a pretty thorough description/troubleshooting paper on the HVAC system.
Fuse #17 to blower relay (Relay XXI) to blower switch to resistor pack to fan.
Fuse #17 to defroster relay (Relay XXII) to fan.
In almost every case:
- If the fan does not work at all, it is usually Fuse #17, its connections, the blower motor or its connections.
- If the fan does not work on any low speed, but works on 4 (highest speed), it is usually a broken wire in the resistor pack, or a connection in that circuit.
- If the fan does not work on any speed setting, but works on DEFROST, the problem is usually a faulty blower relay (Relay XXI)
- If the fan does not work on DEFROST, but works on other settings, the problem is usually a faulty defrost relay (Relay XXII).
If you go to our website, and drill down thru the tips and links to Wally's World, then HVAC, you will find a pretty thorough description/troubleshooting paper on the HVAC system.
06-11-2012, 08:04 PM
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The fan can be powered thru two different paths.
Fuse #17 to blower relay (Relay XXI) to blower switch to resistor pack to fan.
Fuse #17 to defroster relay (Relay XXII) to fan.
In almost every case:
1- If the fan does not work at all, it is usually Fuse #17, its connections, the blower motor or its connections.
2- If the fan does not work on any low speed, but works on 4 (highest speed), it is usually a broken wire in the resistor pack, or a connection in that circuit.
3- If the fan does not work on any speed setting, but works on DEFROST, the problem is usually a faulty blower relay (Relay XXI)
4- If the fan does not work on DEFROST, but works on other settings, the problem is usually a faulty defrost relay (Relay XXII).
If you go to our website, and drill down thru the tips and links to Wally's World, then HVAC, you will find a pretty thorough description/troubleshooting paper on the HVAC system.
Fuse #17 to blower relay (Relay XXI) to blower switch to resistor pack to fan.
Fuse #17 to defroster relay (Relay XXII) to fan.
In almost every case:
1- If the fan does not work at all, it is usually Fuse #17, its connections, the blower motor or its connections.
2- If the fan does not work on any low speed, but works on 4 (highest speed), it is usually a broken wire in the resistor pack, or a connection in that circuit.
3- If the fan does not work on any speed setting, but works on DEFROST, the problem is usually a faulty blower relay (Relay XXI)
4- If the fan does not work on DEFROST, but works on other settings, the problem is usually a faulty defrost relay (Relay XXII).
If you go to our website, and drill down thru the tips and links to Wally's World, then HVAC, you will find a pretty thorough description/troubleshooting paper on the HVAC system.
