HVAC Branch Line Circuit

HVAC BRANCH LINE CIRCUIT


Diagnosis Procedure

1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors of the A/C auto amp. for damage, bend and loose connection (unit side and connector side).
Is the inspection result normal?
YES - GO TO 2.
NO - Repair the terminal and connector.
2.CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect the connector of A/C auto amp.
2. Check the resistance between the A/C auto amp. harness connector terminals.





Is the measurement value within the specification?
YES - GO TO 3.
NO - Repair the A/C auto amp. branch line.
3.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the A/C auto amp. A/C Auto Amp Power and Ground Diagnosis Procedure.
Is the inspection result normal?
YES (Present error)-Replace the A/C auto amp. Service and Repair.
YES (Past error)-Error was detected in the A/C auto amp. branch line.
NO - Repair the power supply and the ground circuit.