Heater fan not working..
#1
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Hi all.
After changing from 4,5 to 4,7 in my 81`US (including wiring loom to engine-CIS) my heater fan won`t start.. The AC pump was used from the old motor, and it was all working before. The fan does not idle when shut off either.. The AC hoses was not disconnected during the change.
Any thoughts anyone?
BR
Jørgen
After changing from 4,5 to 4,7 in my 81`US (including wiring loom to engine-CIS) my heater fan won`t start.. The AC pump was used from the old motor, and it was all working before. The fan does not idle when shut off either.. The AC hoses was not disconnected during the change.
Any thoughts anyone?
BR
Jørgen
#2
Three Wheelin'
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It could be unrelated to the engine swap...
Check the fan resistors under the front cowling, the relay on the HVAC head unit, and the actual linkage/mechanical controls ont he HVAC head unit.
Check the fan resistors under the front cowling, the relay on the HVAC head unit, and the actual linkage/mechanical controls ont he HVAC head unit.
#3
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Linkage and mechanical controls work when the ignition is on.
Thanks!
Jørgen
#4
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1) With ignition switch on, function lever moved to the right (anywhere but off or defrost), see if blower runs on top speed. If so, the problem is probably in the speed control resistor pack under the hood in the blower plenum.
2) If the blower does not run on top speed, move the function lever to DEFROST. If the blower now runs, the problem is probably Relay XXI, the blower relay. If the blower still does not run, the problem is either Fuse 17, its connections, the connections to the blower motor, or the blower motor.
2) If the blower does not run on top speed, move the function lever to DEFROST. If the blower now runs, the problem is probably Relay XXI, the blower relay. If the blower still does not run, the problem is either Fuse 17, its connections, the connections to the blower motor, or the blower motor.
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