DTC B2620: ECU Power Source Circuit Malfunction [08/2013 - ]: Procedure

WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - AUXILIARY BATTERY)

Disconnect the H12 multiplex tilt and telescopic ECU connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage according to the value(s) in the table below.

Standard Voltage

Tester Connection	Condition	Specified Condition
H12-9 (ECUB) - Body ground	Always	11 to 14 V

TEXT IN ILLUSTRATION

*a	Front view of wire harness connector (to Multiplex Tilt and Telescopic ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step

CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - BODY GROUND)

Disconnect the H12 multiplex tilt and telescopic ECU connector.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
H12-8 (GND2) - Body ground	Always	Below 1 Ω

TEXT IN ILLUSTRATION

*a	Front view of wire harness connector (to Multiplex Tilt and Telescopic ECU)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR

OK → See step 3

REPLACE MULTIPLEX TILT AND TELESCOPIC ECU. Refer to REMOVAL [08/2013 - ]