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TROUBLESHOOTING GUIDE
Some air conditioners have a time delayed start (5 seconds), to allow the vehicle’s motor to get up to speed before
engaging the auxiliary alternator.
The air conditioner’s compressor has a built in reset time between stopping and restarting in order to allow refrigerant
pressure to equalize. This is done to prevent starting against high pressures, which will extend the life of the
compressor.
Check all fuses:
5 amp ATC blade fuses, refer to alternator kit for details.
15 amp ATC blade fuse located at Relay 4, located inside the air conditioner.
25 amp ATC blade fuse located at Relay 3, located inside the air conditioner.
Two 100 amp fuses located along 2AWG red wire, and near the battery. Refer to alternator kit for details.
Diodes
There are two diodes in what look like mini blade fuse holders, located inside the A/C unit as part the wire harness.
Do not replace diodes with fuses. The unit will not turn off, draining the battery.
Check all relays:
Relays, located under the cover of the A/C unit.
Timed relays, located under the cover of the A/C unit.
Check alternator output. The alternator should put out 12-14 volts DC.
Check the thermostat electrical connections. The air conditioner will not operate without a functional thermostat.
Check the tension of the alternator belts.
If the evaporator core is frozen solid:
Check the placement of the thermocouple. It should be nested in the evaporator housing and fit between the fins of
the evaporator core.
Check refrigerant pressure:
Compressor will not start if there is insufficient refrigerant pressure.
