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Toyota Tacoma (2015-2018) Service Manual / Differential / Differential System(w/ Rear Differential Lock) / ECU Power Source Circuit

Toyota Tacoma (2015-2018) Service Manual: ECU Power Source Circuit

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION / NOTICE / HINT

NOTICE:

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

PROCEDURE

1.

INSPECT BATTERY

(a) Check the battery voltage.

Standard voltage:

11 to 14 V

NG

CHECK OR REPLACE CHARGING SYSTEM OR BATTERY
OK

2.

CHECK HARNESS AND CONNECTOR (+B AND IG TERMINAL)

(a) Turn the ignition switch off.

(b) Disconnect the 4 wheel drive control ECU connector.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

F13-21 (+B) - Body ground

Always

11 to 14 V

F12-4 (IG) - Body ground

Ignition switch ON

11 to 14 V
Text in Illustration

*a

Front view of wire harness connector

(to 4 Wheel Drive Control ECU)
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (+B OR IG CIRCUIT)
OK

3.

CHECK HARNESS AND CONNECTOR (GND TERMINAL)

(a) Turn the ignition switch off.

(b) Disconnect the 4 wheel drive control ECU connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F12-10 (GND) - Body ground

Always

Below 1 Ω
Text in Illustration

*a

Front view of wire harness connector

(to 4 Wheel Drive Control ECU)
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
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