C1721
Severity: LowAir Suspension Height Sensor Power Circuit Open
Last updated: July 2026
System
Chassis
Subsystem
Chassis Systems
Code Type
Manufacturer-specific
Air Suspension Height Sensor Power Circuit Open
Last updated: July 2026
C1721 is a manufacturer-specific chassis diagnostic trouble code. It is defined as "Air Suspension Height Sensor Power Circuit Open". It falls under the chassis systems area of the vehicle’s chassis system, and its exact meaning can vary between manufacturers.
The onboard diagnostic system sets C1721 when it detects a condition matching "air suspension height sensor power circuit open" in the chassis systems circuit or system. When the fault is confirmed, the module stores the code and, in most cases, turns on a warning light.
This code is generally minor and often relates to a signal, range or performance condition. It should still be inspected, especially if it returns after clearing.
C1721 means "Air Suspension Height Sensor Power Circuit Open". It is a manufacturer-specific chassis trouble code in the chassis systems area.
This code is usually minor, and short-distance driving is often possible, but you should still have it checked — especially if the warning light stays on or the code returns.
There is no single fix. Start by confirming the code with a scan tool, then work through the likely causes and checks above — inspecting wiring, connectors and the relevant components before replacing any parts. On your specific make, confirm the diagnosis before repairs.
You can clear the code with an OBD-II scan tool, but if the underlying fault is still present it will usually return. Clearing without repair is only useful to confirm whether the fault is active.
This information is provided for general reference only. It is not repair advice and may not apply to every make or model. Manufacturer-specific codes can differ. Always confirm a diagnosis with a scan tool and, where needed, a qualified technician before replacing parts.