Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc c1957 lh actuator circuit

Subaru Legacy BN/BS (2015-2019) Service Manual / Vehicle dynamics control (vdc) (diagnostics) / Diagnostic procedure with diagnostic trouble code (dtc) / Dtc c1957 lh actuator circuit

DTC DETECTING CONDITION:

• A fault is detected, if the motor control mismatch occurs during the motor operation.

• A fault is detected if the motor circuit or harness is open or shorted.

TROUBLE SYMPTOM:

Parking brake system does not operate.

NOTE:

This DTC may be stored when the rear brake caliper connector is disconnected regardless of the ignition switch condition (ON/OFF). Perform the Clear Memory Mode after diagnosis if a DTC is recorded. Clear Memory Mode

WIRING DIAGRAM:

NOTE:

For the coupling connector, refer to “WIRING SYSTEM”.

Parking brake / brake fluid level warning light system Parking Brake / Brake Fluid Level Warning Light System

STEP	CHECK	YES	NO
1.CHECK HARNESS (CHECK FOR OPEN CIRCUIT). 1) Turn the ignition switch to OFF. 2) Disconnect the connectors from the VDCCM&H/U and rear brake caliper LH. 3) Measure the resistance between VDCCM&H/U and rear brake caliper LH connector. Connector & terminal (B310) No. 44 — (R154) No. 1: (B310) No. 45 — (R154) No. 2:	Is the resistance less than 1 --	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C1957 LH ACTUATOR CIRCUIT	Repair harness and connector between VDCCM&H/U and rear brake caliper LH connector.
2.CHECK HARNESS (CHECK FOR GROUND SHORT CIRCUIT). Measure the resistance between the rear brake caliper LH connector and chassis ground. Connector & terminal (R154) No. 2 — Chassis ground: (R154) No. 1 — Chassis ground:	Is the resistance 1 M- or more-	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C1957 LH ACTUATOR CIRCUIT	Repair ground short of harness between VDCCM&H/U and rear brake caliper LH connector.
3.CHECK HARNESS (CHECK FOR SHORT CIRCUIT TO POWER SUPPLY). 1) Turn the ignition switch to ON. 2) Measure the voltage between the rear brake caliper LH connector and chassis ground. Connector & terminal (R154) No. 2 (+) — Chassis ground (−): (R154) No. 1 (+) — Chassis ground (−):	Is the voltage less than 1 V-	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C1957 LH ACTUATOR CIRCUIT	Repair short to power supply of harness between VDCCM&H/U and rear brake caliper LH connector.
4.CHECK POOR CONTACT OF CONNECTORS.	Is there poor contact of power supply circuit, ground circuit and VDCCM&H/U connector-	Repair the connector.	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC C1957 LH ACTUATOR CIRCUIT
5.CHECK REAR BRAKE CALIPER. 1) Turn the ignition switch to OFF. 2) Disconnect the connectors from rear brake caliper LH. 3) Measure the resistance between rear brake caliper LH terminals. Terminals No. 1 — No. 2:	Is the resistance less than 100 --	Replace the VDCCM&H/U. VDC Control Module and Hydraulic Control Unit (VDCCM&H/U)	Replace the rear brake caliper LH. Rear Disc Brake Assembly

Dtc c1511 valve relay

DTC DETECTING CONDITION:A fault is detected if valve relay drive voltage failure is detected.TROUBLE SYMPTOM:• ABS does not operate.• EBD does not operate.• VDC does not operate.&bul ...

Dtc c1956 rh actuator circuit

DTC DETECTING CONDITION:• A fault is detected, if the motor control mismatch occurs during the motor operation.• A fault is detected if the motor circuit or harness is open or shorted.TROU ...

Other materials:

Preparation tool
1. GENERAL TOOLTOOL NAMEREMARKSCircuit testerUsed for measuring resistance, voltage and current.NOTE:• When measuring the standby current, prepare a circuit tester which can measure down to 1 mA.• When measuring the standby current for models with keyless access function, prepare an anal ...