Chassis, generic

C0220 ABS Valve Block Supply Voltage

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0220 has not turned up in any accessible J2012 table, NHTSA bulletin or maker index; there is no public evidence of its use. The title refers to the voltage that feeds the solenoid valves of the hydraulic unit. In GM-designed systems such as the TRW EBC450 of the 2011 Saab 9-5, the brake control module itself feeds both the valve coils and the pump motor. A Hella/Lucas patent routes battery voltage to all valves through the contact of a fail-safe relay and checks the switched voltage behind it; a wrong value drops the relay and lights the lamp. Saab's older ESP shows a typical limit for a supply fault, below 9 V for 0.5 s above 6 km/h, stored there as C1532. A weak battery, a blown fuse, poor grounds or charging faults are frequent causes.

Likely causes

Low system voltage from a weak battery or charging fault
Blown fuse or high resistance in the module supply line
Poor ground connection of the brake control module
Faulty valve supply relay or driver inside the module

Symptoms

  • ABS, brake and stability lamps on, often intermittently
  • ABS and traction control unavailable

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–800
Time0.3–2 h

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

Parts involved

abs hydraulic blockabs control modulepower supply wiring

Related codes

C0225C0121C0110

References: saabwisonline.com, patents.google.com, saabwisonline.com.