Air Suspension Control Module (ASCM)

U0401-00-IMPLAUSIBLE DATA RECEIVED FROM ECM/PCM

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
Continuously with the ignition on, one valid CAN message received at least once, and no U0002-88-CAN C Bus Off Performance DTC present.

- Set Condition:
When the Anti-Lock Brake System (ABS) Module detects an incorrect CAN message from the Powertrain Control Module (PCM).





Diagnostic Test

1. VERIFY THE DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, record and erase the DTCs.
3. Cycle the ignition switch from off to on.
4. With the scan tool, read the DTCs.

Is the DTC active at this time?

Yes

- Go To 2

No

- Go To 4

2. CHECK IF BODY CONTROL MODULE (BCM) CAN BUS DTCS ARE PRESENT
1. With the scan tool, read the BCM DTCs.

Are there any BCM CAN BUS DTCs present?

Yes

- Perform the appropriate diagnostic procedure. Testing and Inspection.

No

- Go To 3

3. CHECK IF ENGINE DTCS ARE PRESENT
1. With the scan tool, read Engine DTCs.

Are there any Engine DTCs present?

Yes

- Perform the appropriate diagnostic procedure. Testing and Inspection.

No

- Using the schematics as a guide, check the ASCM pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the Air Suspension Control Module (ASCM). Air Suspension Control Module - Removal.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

4. INTERMITTENT WIRING AND CONNECTORS
1. Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
2. Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
3. Look for the data to change or for the DTC to reset during the wiggle test.
4. While monitoring the scan tool data relative to this circuit, move the selector switch to each position several times.
5. Look for the data to change other than as expected or for the DTC to reset.

Were any problems found?

Yes

- Repair as necessary.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time.