Chassis, generic

C0700 Active Steering Module Communication

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

No public record shows a carmaker using C0700; public J2012 lists, NHTSA bulletins and maker indexes are silent. The title concerns superimposed steering such as the system from the Bosch-ZF venture that BMW introduced on the 2004 5 Series. A compound planetary set in the steering shaft adds an angle from an electric motor that turns the carrier, and an electromagnetic lock holds that carrier still whenever the function is off. A separate controller needs the angles at the wheel and at the pinion plus vehicle and wheel speeds over the network to compute the extra angle. If that exchange breaks down, the logical reaction is to lock the gear set, leaving a fixed ratio with full hydraulic assist; the car steers normally but feels slower at parking speeds. Lost communication is more often filed under U codes.

Likely causes

Damaged bus wiring or connector to the active steering controller
Steering angle or wheel speed message missing from another module
Active steering controller without power or defective

Symptoms

  • Steering warning in the instrument cluster
  • Steering ratio stays fixed, more wheel turns when parking

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,500
Time0.5–4 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

active steering modulecommunication buschassis control module

Related codes

U0126U0130C0460

References: ai-online.com, fenderbender.com.