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

Toyota Tundra Service Manual / Steering / Steering Column / Power Tilt And Power Telescopic Steering Column System / 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
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

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
OK

REPLACE MULTIPLEX TILT AND TELESCOPIC ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
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