C1792: LR Air Spring Solenoid Short to Battery
Diagnostic trouble code C1792 indicates a short circuit to battery positive (B+) in the output circuit of the left rear air spring solenoid. This solenoid controls airflow to the left rear air spring, regulating ride height and suspension stiffness. The suspension control module (SDM) has detected that the voltage on the solenoid control circuit remains high when it should be low, or there is abnormal continuity with the 12V power supply, preventing proper solenoid operation.
1. Commonly Affected Makes
2. Most Common Causes
- Faulty left rear air spring solenoid with internal short circuit
- Solenoid control circuit wiring shorted to battery positive (B+)
- Corroded or bent pins in the solenoid connector causing contact with power circuit
- Suspension control module (SDM) with damaged output transistor stuck in short circuit
- Chafed or damaged wiring harness exposing signal conductors to power conductors
3. Symptoms You Will Notice
- Suspension warning light illuminated on the dashboard
- Uneven ride height, with the left rear corner sitting lower or higher than normal
- Rough or harsh ride quality due to improper air spring pressure
- Suspension system may become inoperative or enter fail-safe mode
4. Step-by-Step Diagnosis
Scan the SDM for stored codes and freeze frame data to confirm C1792 and check for related codes.
Visually inspect the left rear air spring solenoid connector and wiring for corrosion, damage, or pin issues.
Using a multimeter, check for voltage on the solenoid control circuit with the ignition on; if voltage is present when commanded off, suspect a short to B+.
Disconnect the solenoid and measure resistance; compare to specifications (typically 4-12 ohms). An open or shorted reading indicates a faulty solenoid.
If solenoid and wiring check out, test the SDM output by backprobing the connector and monitoring voltage while commanding the solenoid; replace SDM if output is stuck high.
5. Frequently Asked Questions
Is it safe to drive?▼
Driving with code C1792 is not recommended as it can cause unstable ride height and handling, potentially leading to loss of control. The vehicle may enter a reduced-functionality mode. Have it diagnosed promptly.
How much does it cost to fix?▼
Repair costs typically range from $200 to $800, depending on the root cause. A solenoid replacement can be $150-$400, wiring repair $100-$300, and SDM replacement $400-$800 plus programming.