DTC B2793 Back Up Power: Wiring Diagram

WARNING: This page is about a different car, the 2016 Subaru Outback and 2016 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.

Keyless access with push button start system < Ref. to appropriate wiring diagram in SYSTEM WIRING DIAGRAM article. >

Fig 1: Back Up Power - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DIAGNOSTICS PROCEDURE

Step	Check	Yes	No
1 CHECK CURRENT DATA. Check the current data display of «Keyless access with push button start» using Subaru Select Monitor. < Ref. to READ CURRENT DATA . > «ECM power supply voltage (back-up)»	Is «ON» displayed?	Go to step 2 .	Go to step 3 .
2 CHECK DTC. Using the Subaru Select Monitor, clear the memory. < Ref. to CLEAR MEMORY MODE . > Start the engine, and let it idle for 40 seconds or more. Read DTC using the Subaru Select Monitor. < Ref. to READ DIAGNOSTIC TROUBLE CODE (DTC) . >	Is B2793 displayed?	Go to step 3 .	Even if DTC is displayed, 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.
3 CHECK FUSE. Check the fuse. < Ref. to INSPECTION , Relay and Fuse. >	Is the fuse OK?	Go to step 4 .	Replace the fuse. When the replaced fuse is blown immediately, check the power supply circuit for short-circuited.
4 CHECK HARNESS. Disconnect the keyless access control module connector. Using a tester, measure the voltage between the keyless access control module connector and chassis ground. Connector & terminal (i241) No. 40 (+) - Chassis ground (-):	Is the voltage 9.5 - 16 V?	Replace the keyless access control module. < Ref. to KEYLESS ACCESS CONTROL MODULE . >	Repair or replace the open circuit of harness.