C1556-14

C1556-14-RIDE HEIGHT AIR PRESSURE SENSOR - CIRCUIT SHORT TO GROUND OR OPEN

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





- When Monitored:
Ignition on. Battery voltage between 9 and 16 volts.

- Set Condition:
When the Air Suspension Control Module (ASCM) detects the pressure sensor signal is shorted to ground or an open circuit while ignition is in the Run position.





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 8

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

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

No

- Go To 3

3. (Y10) 5 VOLT 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 (Y10) 5 Volt Supply between the ASCM C2 harness connector and the Air Suspension Solenoid Assembly harness connector.

Is the resistance above 5.0 Ohms?

Yes

- Repair the (Y10) 5 Volt Supply circuit for an open or high resistance.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Go To 4

4. (Y18) PRESSURE SENSOR SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE




1. Measure the resistance of the (Y18) Pressure Sensor Signal 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 (Y18) Pressure Sensor Signal circuit for an open or high resistance.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Go To 5

5. (Y18) PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND




1. Measure the resistance between ground and the (Y18) Pressure Sensor Signal circuit.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (Y18) Pressure Sensor Signal circuit for a short to ground.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Go To 6

6. AIR SUSPENSION SOLENOID ASSEMBLY PRESSURE SENSOR SIGNAL




1. Connect the Air Suspension Solenoid Assembly harness connector.
2. Measure the resistance between the (Y18) Pressure Sensor Signal circuit and the (Y13) Pressure Sensor Return circuit at the ASCM C2 harness connector.

Is the resistance above 60k Ohms?

Yes

- Replace the Air Suspension Solenoid Assembly. Compressor Assembly Valve Block - Removal.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

- Go To 7

7. AIR SUSPENSION SOLENOID ASSEMBLY 5 VOLT SUPPLY




1. Measure the resistance between the (Y10) 5 Volt Supply circuit and the (Y13) Pressure Sensor Return circuit at the ASCM C2 harness connector.

Is the resistance above 60k Ohms?

Yes

- Replace the Air Suspension Solenoid Assembly. Compressor Assembly Valve Block - Removal.
- Perform the ASCM VERIFICATION TEST. ASCM Verification Test.

No

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

8. 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.