DTC P0328 Knock Sensor 1 Circuit High (Bank 1 Or Single Sensor): Wiring Diagram

WARNING: This page is about a different car, the 2013 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

Engine electrical system, non-turbo model < Refer to appropriate SYSTEM WIRING DIAGRAM. >

Fig 1: Knock Sensor 1 Circuit High - Wiring Diagram (Bank 1 Or Single Sensor)

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTIC PROCEDURE

Step	Check	Yes	No
1 CHECK HARNESS BETWEEN ECM AND KNOCK SENSOR CONNECTOR. Turn the ignition switch to OFF. Disconnect the connector from ECM. Measure the resistance between ECM connectors. Connector & terminal (B137) No. 2 - (B134) No. 29:	Is the resistance less than 500 kΩ?	Go to step 2 .	Go to step 3 .
2 CHECK KNOCK SENSOR. Disconnect the connector from the knock sensor. Measure the resistance between knock sensor terminals. Terminals No. 1 - No. 2:	Is the resistance less than 500 kΩ?	Replace the knock sensor. < Refer to KNOCK SENSOR . >	Repair the short circuit to ground in harness between ECM and knock sensor connector. NOTE: The harness between both connectors are shielded. Remove the shield and repair the short circuit of harness.
3 CHECK INPUT SIGNAL OF ECM. Connect the connector to ECM. Turn the ignition switch to ON. Measure the voltage between ECM and chassis ground. Connector & terminal (B137) No. 2 (+) - Chassis ground (-):	Is the voltage 2 V or more?	Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.	Repair the poor contact of ECM connector.