No Response From SCM (Steering Control Module)

*NO RESPONSE FROM SCM (STEERING CONTROL MODULE)





For a complete wiring diagram Consult Diagrams/Electrical.





Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.

With the scan tool, select ECU view.

NOTE: A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.

Does the scan tool display a red X next to the module?

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.

2. FUSED IGNITION SWITCH CIRCUIT OPEN OR SHORTED




Disconnect the Steering Control Module C1 harness connector.
Using a 12-volt test light connected to ground, check the Fused Ignition Switch circuit.
Does the test light illuminate brightly?

Yes

- Go To 3

No

- Repair the Fused Ignition Switch circuit for an open or short.
- Perform the BODY VERIFICATION TEST - VER 1.Verification Tests.

3. GROUND CIRCUIT OPEN




Turn the ignition off.
Disconnect the Steering Control Module C2 harness connector.
Using a 12-volt test light connected to 12-volts, check the ground circuits.
Does the test light illuminate brightly for each circuit?

Yes

- Go To 4

No

- Repair the ground circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1.Verification Tests.

4. CAN C BUS (+) CIRCUIT OPEN




Disconnect the Ignition Switch C4 harness connector.
Measure the resistance of the CAN C Bus (+) circuit between the Ignition Switch connector and the SCM connector.
Is resistance below 5.0 ohms?

Yes

- Go To 5

No

- Repair the CAN C Bus (+) circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1.Verification Tests.

5. CAN C BUS (-) CIRCUIT OPEN




Measure the resistance of the CAN C Bus (-) circuit between the Ignition Switch connector and the SCM connector.
Is resistance below 5.0 ohms?

Yes

- Replace the Steering Control Module.
- Perform the BODY VERIFICATION TEST - VER 1.Verification Tests.

No

- Repair the CAN C Bus (-) circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1.Verification Tests.