C0700
Active Steering Module Communication
A communication fault between the chassis control module and the active steering module has been detected. Active steering varies the steering ratio with speed, and a fault disables this assistance and may store secondary codes in other modules.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: hard
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Communication bus faultCommon
- Active steering module failedPossible
- Power supply or ground fault to moduleLess likely
Parts involved
- Active Steering Module
- Communication Bus
- Chassis Control Module
C0700 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.