Air Suspension LR Height Sensor Circuit Open
The left rear air suspension height sensor isn't sending a signal to the computer, like a broken speedometer that can't tell the car how fast it's going. The vehicle can't properly adjust suspension stiffness and ride height for that corner.
The ECU monitors voltage signals from the left rear height sensor to detect suspension position and adjust air pressure accordingly. When the circuit opens (wire breaks or connector fails), the ECU receives no signal and cannot regulate that corner's suspension height. The system defaults to a fault state and disables automatic leveling.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor voltage signal | 0.5-4.5 volts (variable with suspension height) | No signal or out-of-range voltage |
| Circuit resistance | Less than 10 ohms end-to-end | Open circuit (infinite resistance) |
Code C1894 is classified as a serious fault. If your check engine light is flashing — not just steady — pull over safely and do not continue driving. A flashing CEL indicates an active misfire or critical failure that can cause catalytic converter damage within minutes or permanent engine harm within miles. Contact a certified mechanic immediately. Do not attempt roadside repairs on high-severity codes unless you are trained to do so.
Once the fault is repaired, C1894 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.