AC Not Blowing
06-23-2008, 10:21 AM
#1
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Join Date: Mar 2005
Location: Ann Arbor, MI
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AC Not Blowing
Greetings,
Car is an '80 SC, air worked fine when stored for the winter last fall and now when I rotate the a/c switch to the on postions, no air blows out.
I checked all fuses and even swapped known-good relays at the fuse box to see if that was the problem, but still no fan.
Could it be the switch or could it be a connection at the fan?
Any and all help is greatly appreciated!
Sebastian Gaeta
Car is an '80 SC, air worked fine when stored for the winter last fall and now when I rotate the a/c switch to the on postions, no air blows out.
I checked all fuses and even swapped known-good relays at the fuse box to see if that was the problem, but still no fan.
Could it be the switch or could it be a connection at the fan?
Any and all help is greatly appreciated!
Sebastian Gaeta
07-20-2008, 04:59 PM
#2
1) Open the front, pull back the carpets, open the smuggler door, on the RH (your left) forward corner on the top of the evaporator box is a black plastic covered wire harness with a white amp connector. Unplug the connector. Looking at the amp connector side leading into the evaporator lid you'll see two male spades, the vertical one has red wire and the horizontal spade as a brown wire. Using either your vehicle's batter or an external power supply, apply 12vdc positive to the vertical (red wire) spade, ground the horizontal spade (brown wire) to your battery (if you are using it) or power supplies negative lead. If the evaporator motor spins the problem is south of circuit providing power to the evap motor. If the evap motor does no spin you could try giving it a jump start my physically spinning the fan (you would have to remove the evap blower hose off the outlet and stick you fingers in there .... which can be interesting, or remove the top of the evap box which is almost as much fun. If the motor takes off with a jump start or if its still DOA then its time for a new evap fan motor.
2) When you have the ac thermostat on max cold (**** turned fully CW) and the evap fan motor **** is turned on, (ign. key on too naturally) check to see if the compressor clutch is snapping or engaging (outer hub moves in toward the clutch pulley). If the clutch hub snaps in then your problem (w'ell assume the evap fan motor not spinning was your annunciator) is north of the ac clutch circuit. If clutch hub does not snap in, disconnect the power wire to the ac clutch and use 12vdc positive to the wire on the compressor and also provide a negative ground to the compressor's body from the same power source. If the clutch hub snaps in with an alternate power source then the problem is north of the ac clutch circuit. If the clutch does not snap with an alternate power source you need a new compressor (i'd shy away from used clutches or clutch coils as most reasons for failure are related to the compressor overheating and that spells toast down the road).
3) You can also check for power to the compressor, with the ign key on, thermostat on max cold and evap blower motor turned on. If you have no power to the power lead (located by the oil filter), then you work north in the circuit to the ac relay in the smugglers box or faulty ac thermostat switch; we'll assume you already checked the fuse in the front trunk on the fuse panel.
pm if you need more help.
2) When you have the ac thermostat on max cold (**** turned fully CW) and the evap fan motor **** is turned on, (ign. key on too naturally) check to see if the compressor clutch is snapping or engaging (outer hub moves in toward the clutch pulley). If the clutch hub snaps in then your problem (w'ell assume the evap fan motor not spinning was your annunciator) is north of the ac clutch circuit. If clutch hub does not snap in, disconnect the power wire to the ac clutch and use 12vdc positive to the wire on the compressor and also provide a negative ground to the compressor's body from the same power source. If the clutch hub snaps in with an alternate power source then the problem is north of the ac clutch circuit. If the clutch does not snap with an alternate power source you need a new compressor (i'd shy away from used clutches or clutch coils as most reasons for failure are related to the compressor overheating and that spells toast down the road).
3) You can also check for power to the compressor, with the ign key on, thermostat on max cold and evap blower motor turned on. If you have no power to the power lead (located by the oil filter), then you work north in the circuit to the ac relay in the smugglers box or faulty ac thermostat switch; we'll assume you already checked the fuse in the front trunk on the fuse panel.
pm if you need more help.