Diagnostic Test

TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
  NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.
2. With the scan tool, select System select.
  NOTE: If an ECU is grayed out, it is not communicating, indicating that the module is not active on the Bus network.
Q: Is the ECU grayed out?

Yes :
- Go To 2
No :
- The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
(F504) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED

Fig 1: Checking Fused Ignition Switch Output Circuit Open Or Shorted
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
1. Turn the ignition off.
  NOTE: Check IPM fuses before continuing.
2. Disconnect the A/C Heater Control C1 harness connector.
3. Turn the ignition on.
4. Using a 12-volt test light connected to ground, check the (F504) Fused Ignition Switch Output circuit.
Q: Does the test light illuminate brightly?

Yes :
- Go To 3
No :
- Repair the (F504) Fused Ignition Switch Output circuit for an open or short.
- Perform BODY VERIFICATION TEST - VER 1 . (Refer to ELECTRONIC CONTROL MODULES/MODULE - FRONT CONTROL/DIAGNOSIS AND TESTING).
(Z24) GROUND CIRCUIT OPEN

Fig 2: Checking Ground Circuit Open
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
1. Turn the ignition off.
2. Using a 12-volt test light connected to 12-volts, check the (Z24) ground circuit.
Q: Does the test light illuminate brightly?

Yes :
- Go To 4
No :
- Repair the (Z24) ground circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1 . (Refer to ELECTRONIC CONTROL MODULES/MODULE - FRONT CONTROL/DIAGNOSIS AND TESTING).
(D55) AND (D54) CAN B BUS CIRCUITS OPEN

Fig 3: Checking CAN B Bus Circuits Open
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

NOTE: One open circuit will not cause this condition.
1. Measure the voltage between the (D54) CAN B Bus (-) circuit and ground.
2. Measure the voltage between the (D55) CAN B Bus (+) circuit and ground.
Q: Is there any voltage present on either circuit?

Yes :
- Replace the A/C Heater Control in accordance with the service information.
- Perform BODY VERIFICATION TEST - VER 1 . (Refer to ELECTRONIC CONTROL MODULES/MODULE - FRONT CONTROL/DIAGNOSIS AND TESTING).
No :
- Repair the (D55) and (D54) CAN B Bus circuits for an open. Inspect the connector for damage.
- Perform BODY VERIFICATION TEST - VER 1 . (Refer to ELECTRONIC CONTROL MODULES/MODULE - FRONT CONTROL/DIAGNOSIS AND TESTING).