Defect Code 12

Defect Code 12:

Explanation:

Rear left plunger solenoid valve malfunction

Possible cause:

Short or break on control wire to plunger hydraulic unit
Short or break on B+ supply wire from ABS hydraulic unit to plunger hydraulic unit
Solenoid valve defective

Troubleshooting:

Switch off ignition and detach control unit connector.

Measure resistance at the control unit connector (X11) Pin 21/23;
Nominal value: 0.8 ... 1.8 Ohm

Measure inductance at the control unit connector (X11) Pin 21/23;
Nominal value: Approx. 20 mH

If necessary, remove plunger hydraulic unit, ensure plug connections is firmly fitted and check for corrosion, measure internal resistance of the solenoid valve directly at the plunger hydraulic unit.

Replace ABS/ASC+T control unit If no defect can be found on the wiring harness side.