DTC P1518 Starter Switch Circuit Low Input: Wiring Diagram

WARNING: This page is about a different car, the 2012 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Starter Switch Circuit Low Input - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSIS PROCEDURE

Step	Check	Yes	No
1 CHECK FOR ANY OTHER DTC ON DISPLAY.	Is any other DTC displayed?	Check DTC using "List of Diagnostic Trouble Code (DTC)". < refer to LIST OF DIAGNOSTIC TROUBLE CODE (DTC) . >	Go to step 2 .
2 CHECK HARNESS BETWEEN ECM AND STARTER RELAY CONNECTOR. Turn the ignition switch to OFF. Remove the starter relay. Disconnect the connectors from ECM and starter motor. Measure the resistance of harness between ECM and starter relay connector. Connector & terminal (B136) No. 16 - (B225) No. 10: NOTE: For AT model, place the select lever in "P" range or "N" range.	Is the resistance less than 1 Ω?	Go to step 3.	NOTE: Check the following item and repair or replace if necessary. Open circuit of harness between ECM and starter relay connector Poor contact of coupling connector
3 CHECK HARNESS BETWEEN ECM AND STARTER RELAY CONNECTOR. Measure the resistance between ECM and chassis ground. Connector & terminal (B136) No. 16 - Chassis ground:	Is the resistance 1 MΩ or more?	Repair the poor contact of ECM connector.	Repair the short circuit to ground in harness between ECM and starter relay connector.