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 front air control 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 front air control.
2.Check the resistance between the front air control harness connector terminals.
-Models with auto A/C





-Models with manual 3 control dial system





-Models with manual 2 control dial system





Is the measurement value within the specification?
YES- GO TO 3.
NO- Repair the front air control branch line.

3. CHECK POWER SUPPLY AND GROUND CIRCUIT

Check the power supply and the ground circuit of the front air control. Refer to the following.
- Models with automatic air conditioner: Power Supply And Ground Circuit For Controller
- Models with manual air conditioner - type 1: Manual A/C Type 1
- Models with manual air conditioner - type 2: Manual A/C Type 2
Is the inspection result normal?
YES (Present error)-Replace the front air control. Service and Repair.
YES (Past error)-Error was detected in the front air control branch line.
NO- Repair the power supply and the ground circuit.