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Home >> Jeep >> 2019 >> Grand Cherokee Trackhawk >> Repair and Diagnosis >> Suspension >> Suspension Control Systems >> (Air Suspension Control Module (ASCM) - Electrical Diagnostics) >> DTC Troubleshooting >> C155E-13-Ride Height Pressure Vent Control - Circuit Open >> Diagnostic Test

Diagnostic Test

  1. VERIFY THE DTC IS ACTIVE 
    1. Turn the ignition on.
    2. With the scan tool, record and erase DTCs.
    3. With the scan tool, read the DTCs in the ASCM.

      Is the DTC active at this time?

      Yes 

      • Go To  2

      No 

      • Go To  6
  2. AIR SUSPENSION SOLENOID ASSEMBLY HARNESS CONNECTOR 
    NOTE:

    Make sure the Air Suspension Solenoid Assembly harness connector is connected correctly.

    1. Turn the ignition off.
    2. Inspect the Air Suspension Solenoid Assembly harness connector for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.

      Were any problems found?

      Yes 

      No 

      • Go To  3
  3. (Y30) AIR SPRING VALVE SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE 
    1. Disconnect the Air Suspension Solenoid Assembly harness connector.
    2. Disconnect the ASCM C2 harness connector.
    3. Measure the resistance of the (Y30) 12V Valve Power Supply circuit between the ASCM C2 harness connector and the Air Suspension Solenoid Assembly harness connector.

      Is the resistance above 5.0 Ohms?

      Yes 

      • Repair the (Y30) 12V Valve Power Supply circuit for an open or high resistance.
      • Perform the ASCM VERIFICATION TEST. Refer to ASCM VERIFICATION TEST .

      No 

      • Go To  4
  4. (Y35) AMBIENT VALVE CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 
    1. Measure the resistance of the (Y35) Ambient Valve Control circuit between the ASCM C2 harness connector and the Air Suspension Solenoid Assembly harness connector.

      Is the resistance above 5.0 Ohms?

      Yes 

      • Repair the (Y35) Ambient Valve Control circuit for an open or high resistance.
      • Perform the ASCM VERIFICATION TEST. Refer to ASCM VERIFICATION TEST .

      No 

      • Go To  5
  5. AIR SUSPENSION VALVE BLOCK 
    1. Connect the Air Suspension Solenoid Assembly harness connector.
    2. Measure the resistance between (Y30) 12 Volt Power Supply circuit and the (Y35) Ambient Valve Control circuit at the ASCM C2 harness connector.

      Is the resistance below 30 Ohms?

      Yes 

      No 

  6. 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 

      No 

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