Toyota Tacoma 2015-2018 Service Manual: Transfer Shift Motor Control Circuit Circuit Open (P17A8)

Toyota Tacoma 2015-2018 Service Manual / Vf2cm Transfer / Touch Select 2-4 And High-low System / Transfer Shift Motor Control Circuit Circuit Open (P17A8)

DESCRIPTION

This DTC is output when an open circuit in the transfer shift motor drive circuit is detected.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
P17A8	Transfer Shift Motor Control Circuit Circuit Open	Diagnosis Condition: While switching between 2WD and H4 or while switching between H4 and L4 (transfer shift motor operating) with the ignition switch turned to ON Malfunction Status: Open circuit in the transfer shift motor drive circuit Malfunction Time: 0.03 seconds or more Other: 1 trip detection logic	Wire harness and connector 4 wheel drive control ECU Transfer shift actuator assembly

WIRING DIAGRAM

Refer to DTC P17A9 (See page PROCEDURE ).

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - TRANSFER SHIFT ACTUATOR ASSEMBLY)

(a) Disconnect the F12 4 wheel drive control ECU connector.

(b) Disconnect the T4 transfer shift actuator assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F12-8 (TM1) - T4-2 (TM1)	Always	Below 1 Ω
F12-7 (TM2) - T4-1 (TM2)	Always	Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.	INSPECT TRANSFER SHIFT ACTUATOR ASSEMBLY (TRANSFER SHIFT MOTOR)

(a) Disconnect the T4 transfer shift actuator assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
2 (TM1) - 1 (TM2)	Always	1.5 to 10 Ω

Text in Illustration

*a	Component without harness connected (Transfer Shift Actuator Assembly)

REPLACE 4 WHEEL DRIVE CONTROL ECU

REPLACE TRANSFER SHIFT ACTUATOR ASSEMBLY

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