Diagnostic Test

WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY THE DTC IS ACTIVE
NOTE:
If multiple DTCs are present, inspect the wiring and harness connector at the Air Suspension Compressor.
1. Turn the ignition on.
2. With the scan tool, record and erase DTCs.
3. With the scan tool, read ASCM DTCs.
  Is the DTC active at this time?
  
  Yes
  - Go To 2
  No
  - Go To 5
(K374) COMPRESSOR RELIEF VALVE SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Air Suspension Compressor Assembly harness connector.
3. Disconnect the ASCM C3 harness connector.
4. Turn the ignition on.
5. Measure the voltage between ground and the (K374) Compressor Relief Valve Signal circuit.
  Is any voltage present?
  
  Yes
  - Repair the (K374) Compressor Relief Valve Signal circuit for a short to voltage.
  - Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE - ASCM VERIFICATION TEST .
  No
  - Go To 3
(K375) COMPRESSOR RELIEF VALVE RETURN CIRCUIT SHORTED TO (K374) COMPRESSOR RELIEF VALVE SIGNAL CIRCUIT
1. Measure the resistance between (K375) Compressor Relief Valve Return circuit and the (K374) Compressor Relief Valve Signal circuit at the ASCM C3 harness connector.
  Is the resistance below 5 Ohms?
  
  Yes
  - Repair the short between the (K375) Compressor Relief Valve Return circuit and the (K374) Compressor Relief Valve Signal circuit.
  - Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE - ASCM VERIFICATION TEST .
  No
  - Go To 4
AIR SUSPENSION COMPRESSOR ASSEMBLY
1. Connect the Air Suspension Compressor Assembly harness connector.
2. Measure the resistance between (K375) Compressor Relief Valve Return circuit and the (K374) Compressor Relief Valve Signal circuit at the ASCM C3 harness connector.
  Is the resistance below 15 Ohms?
  
  Yes
  - Replace the Air Suspension Compressor Assembly in accordance with the Service Information. Refer to COMPRESSOR ASSEMBLY, AIR SUSPENSION, REMOVAL .
  - Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE - ASCM VERIFICATION TEST .
  No
  - Replace the Air Suspension Control Module (ASCM) in accordance with the Service Information. Refer to MODULE, AIR SUSPENSION CONTROL (ASCM), REMOVAL .
  - Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE - ASCM VERIFICATION TEST .
INTERMITTENT WIRING, CONNECTORS AND AIR LINES
1. Inspect the intake and exhaust air lines for restrictions, debris, or contamination.
2. Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
3. Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
4. Look for the data to change or for the DTC to reset during the wiggle test.
5. While monitoring the scan tool data relative to this circuit, move the air suspension switch to each position several times.
6. 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 - ASCM VERIFICATION TEST .
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time.