Chassis, generic

C0016 Right Front Hydraulic Release Too Long

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

Set when the ABS modulator cannot release pressure at the right front wheel within the expected time during a control cycle, the right front equivalent of C0012. After commanding the right front outlet valve to dump pressure the module expects wheel speed to recover and line pressure to fall; if the release exceeds the calibrated time limit it infers a sticking valve, a restricted hydraulic path or an accumulator/pump that cannot take fluid. The module disables ABS and stability control and sets the ABS warning lamp. No manufacturer documents this code publicly. A patent on ABS low-pressure accumulators shows why release can stall: once the accumulator pressure is high, fluid no longer leaves the wheel through the outlet valve as requested.

Likely causes

Outlet valve sticking or slow
Restricted hydraulic path or contaminated fluid
Pump or accumulator cannot accept fluid

Symptoms

  • ABS warning lamp on
  • ABS and stability control disabled
  • Extended or firm pedal during hard braking

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€300–1,800
Time2–4 h

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

Parts involved

rf abs outlet valvehcu

Related codes

C0014C0015C0012

References: rosap.ntl.bts.gov, patents.google.com, en.wikipedia.org.