No response From ACSM (Air Suspension Control Module)

NO RESPONSE FROM ACSM (AIR SUSPENSION CONTROL MODULE)

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









Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION

NOTE: Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.

1. Turn the ignition on.

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

2. With the scan tool, read the module status.

NOTE: Check the BCM for any active CAN C hardware DTCs, perform DTC before proceeding.

Does the scan tool indicate that the module is active on the bus?

Yes

- The no response condition is not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.

No

- Go To 2

2. CHECK THE (A206) FUSED B(+) CIRCUIT FOR AN OPEN OR SHORT
1. Turn the ignition off.
2. Disconnect the Air Suspension Control Module (ASCM) C2 harness connector.
3. Using a 12-volt test light connected to ground, check the (A206) Fused B(+) circuit.

Does the test light illuminate brightly for each circuit?

Yes

- Go To 4

No

- Repair the (A206) Fused B(+) circuit for an open or short.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

3. CHECK THE (F944) IGNITION RUN/START CONTROL OUTPUT CIRCUIT FOR OPEN OR SHORT
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the (F944) Ignition Run/Start Control Output circuit.

Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the (F944) Ignition Run/Start Control Output circuit for an open or short.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

4. CHECK THE (Z906) GROUND CIRCUIT FOR AN OPEN
1. Using a 12-volt test light connected to 12-volts, check the (Z906) Ground circuit.

Does the test light illuminate brightly for each circuit?

Yes

- Go To 5

No

- Repair the Ground circuits for an open.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

5. CHECK THE (D151) CAN C BUS (+) CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the Star CAN C IP C5 harness connector.
3. Measure the resistance of the (D151) CAN C Bus (+) circuit between the Star CAN C Bus (+) C5 harness connector and the ASCM harness connector.

Is resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (D151) CAN C Bus (+) circuit for an open.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

6. CHECK THE (D150) CAN C BUS (-) CIRCUIT FOR AN OPEN
1. Measure the resistance of the (D150) CAN C Bus (-) circuit between the Star CAN C Bus (-) C5 harness connector and the ASCM harness connector.

Is resistance below 5.0 Ohms?

Yes

- Replace the Air Suspension Control Module (ASCM). Air Suspension Control Module - Removal.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Repair the (D150) CAN C Bus (-) circuit for an open.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.