Chassis, generic

C0307 Inlet Valve Rear Right Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

C0307 has no public trace: not in the accessible J2012 lists, not in GM's PIP5094 or AA1Car's GM table, and not in the NHTSA bulletin index. Described here is the rear right inlet valve of the title. In an ESP valve block it does more than ABS work: Saab explains for the 9-5 that both valves of each rear wheel are also driven during stability interventions, so that pressure can be shaped at all four corners while the pump runs. A rear right inlet valve that answers slowly therefore spoils both ABS stops and stability corrections that brake the right rear wheel. The self-test at ignition-on catches coil faults; hydraulic slowness shows up during regulation. Either way ABS and ESP are switched off with their lamps.

Likely causes

Rear right inlet valve slowed by dirt or aged fluid
Coil of the valve or brake module output defective
Poor contact between brake module and valve block

Symptoms

  • ABS and stability control lamps on
  • Stability control unavailable

Repair estimate

DifficultyHardWorkshop job
Parts and labour€150–1,500
Time1–3 h

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

Parts involved

rr abs inlet valveabs hydraulic blockabs control module

Related codes

C0305C0309C0303

References: saabwisonline.com, saabwisonline.com, bosch-mobility.com.