Diagnostic Test
WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- VERIFY THE DTC IS ACTIVE
- AIR SUSPENSION COMPRESSOR ASSEMBLY HARNESS CONNECTOR NOTE:
Make sure the Air Suspension Compressor Assembly harness connector is connected correctly.
- Turn the ignition off.
- Inspect the Air Suspension Compressor Assembly harness connector for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
Were any problems found?
Yes
- Repair as necessary.
- Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 3
- (K374) COMPRESSOR RELIEF VALVE SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE
- Disconnect the Air Suspension Compressor Assembly harness connector.
- Disconnect the ASCM C3 harness connector.
- Measure the resistance of the (K374) Compressor Relief Valve Signal circuit between the ASCM C3 harness connector and the Air Suspension Compressor Assembly harness connector.
Is the resistance above 5 Ohms?
Yes
- Repair the (K374) Compressor Relief Valve Signal circuit for an open or high resistance.
- Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 4
- (K375) COMPRESSOR RELIEF VALVE RETURN CIRCUIT OPEN OR HIGH RESISTANCE
- Measure the resistance of the (K375) Compressor Relief Valve Return circuit between the ASCM C3 harness connector and the Air Suspension Compressor Assembly harness connector.
Is the resistance above 5 Ohms?
Yes
- Repair the (K375) Compressor Relief Valve Return circuit for an open or high resistance.
- Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 5
- Measure the resistance of the (K375) Compressor Relief Valve Return circuit between the ASCM C3 harness connector and the Air Suspension Compressor Assembly harness connector.
- AIR SUSPENSION COMPRESSOR ASSEMBLY
- Connect the Air Suspension Compressor Assembly harness connector.
- Measure the resistance between (K374) Compressor Relief Valve Signal circuit and the (K375) Compressor Relief Valve Return circuit at the ASCM C2 harness connector.
Is the resistance below 15 Ohms?
Yes
- Replace the Air Suspension Compressor Assembly in accordance with the Service Information. (Refer to REMOVAL ).
- Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace the Air Suspension Control Module (ASCM) in accordance with the Service Information. Refer to MODULE, AIR SUSPENSION CONTROL, REMOVAL .
- Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- INTERMITTENT WIRING, CONNECTORS AND AIR LINES
- Inspect the intake and exhaust air lines for restrictions, debris, or contamination.
- Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
- Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
- Look for the data to change or for the DTC to reset during the wiggle test.
- While monitoring the scan tool data relative to this circuit, move the air suspension switch to each position several times.
- 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. Refer to STANDARD PROCEDURE .
No
- Test complete, the condition or conditions that originally set this DTC are not present at this time.