Toyota Tundra Service Manual: ECU Power Source Circuit Malfunction (B2620)

DESCRIPTION

The ECU power source circuit supplies positive (+) voltage to the multiplex tilt and telescopic ECU.

DTC Code	Detection Condition	Trouble Area
B2620	The voltage of the ECU power source drops to 8 V or less and this condition continues for 10 seconds or more.	ECU-DCC NO. 2 fuse Harness or connector Multiplex tilt and telescopic ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

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

(a) Disconnect the J174 multiplex tilt and telescopic ECU connector.

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

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
J174-9 (ECUB) - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

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

(a) Disconnect the J174 multiplex tilt and telescopic ECU connector.

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

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
J174-8 (GND2) - Body ground	Always	Below 1 Ω

REPLACE MULTIPLEX TILT AND TELESCOPIC ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

Toyota Tundra Service Manual > Power Window Control System(w/o Jam Protection Function): Operation Check
OPERATION CHECK 1. CHECK WINDOW LOCK SWITCH (a) Check that the front passenger side power window and rear power windows cannot be operated when the window lock switch of the master switch is pressed. OK: Operation of front passenger side power window and rear power windows are disabled. (b) Check th ...

Toyota Tundra Owners Manual