Circuit/System Testing
- Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
- Disconnect the X1 harness connector at the K8 Blower Motor Control Module.
- Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- If 10 Ω or greater
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground connection.
- If less than 10 Ω
- Ignition ON.
- Verify a test lamp illuminates between the B+ circuit terminal 6 and ground.
- If the test lamp does not illuminate and the circuit fuse is good
- Ignition OFF, remove the test lamp.
- Test for less than 2 Ω in the B+ circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
- If the test lamp does not illuminate and the circuit fuse is open
- Ignition OFF, remove the test lamp.
- Test for infinite resistance between the B+ circuit terminal 6 and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance
- Disconnect the X2 harness connector at the K8 Blower Motor Control Module and disconnect the harness connector at the M8 Blower Motor.
- Test for infinite resistance between the M8 Blower Motor control circuit terminal B and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, test or replace the M8 Blower Motor.
- If the test lamp illuminates
- Ignition OFF, remove the test lamp. Disconnect the X2 harness connector at the K33 HVAC Control Module, ignition ON.
- Test for less than 1 V between the K8 Blower Motor Control Module control circuit terminal 3 and ground.
- If 1 V or greater
Repair the short to voltage on the circuit.
- If less than 1 V
- If 1 V or greater
- Ignition OFF.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance
Repair the short to ground on the circuit.
- If infinite resistance
- If less than infinite resistance
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater
Repair the open/high resistance in the circuit.
- If less than 2 Ω
- If 2 Ω or greater
- Ignition OFF, connect the harness connectors at the K8 Blower Motor Control Module and the K33 HVAC Control Module. Disconnect the harness connector at the M8 Blower Motor, ignition ON and blower ON.
- Verify a test lamp illuminates between the B+ circuit terminal A and ground.
- If the test lamp does not illuminate
- Ignition OFF, disconnect the X2 harness connector at the K8 Blower Motor Control Module.
- Test for less than 2 Ω in the B+ circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω replace the K8 Blower Motor Control Module.
- If the test lamp illuminates
- Connect a test lamp between the control circuit terminal B and the B+ circuit terminal A.
- Verify the test lamp becomes progressively brighter as the blower speed is increased and progressively dimmer as the blower speed is decreased.
- If the test lamp does not illuminate
- Ignition OFF, disconnect the X2 harness connector at the K8 Blower Motor Control Module, ignition ON.
- Test for less than 1 V between the M8 Blower Motor control circuit terminal B and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω replace the K8 Blower Motor Control Module.
- If the test lamp illuminates, but does not change in brightness
- Ignition OFF, disconnect the X2 harness connector at the K8 Blower Motor Control Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, replace the K8 Blower Motor Control Module.
- If the test lamp changes in brightness as the blower speed is changed
- Test or replace the M8 Blower Motor.