DTC C0074 Pressure Sensor Open Circuit: Wiring Diagram

Fig 1: Identifying Ignition Switch, VDCCM And H/U - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE CHART

Step	Check	Yes	No
1 CHECK THE VDCCM&H/U POWER VOLTAGE. Turn the ignition switch to OFF. Disconnect the connector from the VDCCM&H/U. Turn the ignition switch to ON. Measure the voltage between VDCCM&H/U connector and chassis ground. Connector & terminal (B310) No. 1 (+) - Chassis ground (-):	Is the voltage 10 - 15 V?	Go to step 2.	Repair the power supply circuit.
2 CHECK THE VDCCM&H/U GROUND CIRCUIT. Turn the ignition switch to OFF. Measure the resistance between VDCCM&H/U connector and chassis ground. Connector & terminal (B310) No. 43 - Chassis ground:	Is the resistance less than 0.5 Ω?	Go to step 3.	Repair the VDCCM&H/U ground harness.
3 CHECK PRESSURE SENSOR. Connect the Subaru Select Monitor to the vehicle. Select {Current Data Display & Save} in Subaru Select Monitor. Depress the brake pedal. Read the pressure switch output in Subaru Select Monitor.	Do the values on the monitor display change when the pedal is depressed?	Go to step 4.	Replace the VDCCM&H/U. <Ref. to VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM&H/U) .>
4 CHECK THE VDCCM&H/U. Connect all the connectors. Erase the memory. Perform the INSPECTION MODE . Read the DTC.	Is the same DTC displayed?	Replace the VDCCM&H/U. <Ref. to VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM&H/U) .>	Go to step 5.
5 CHECK OTHER DTC DETECTION.	Is any other DTC displayed?	Perform the diagnosis according to DTC.	Temporary poor contact occurs.