Toyota Tacoma (2015-2018) Service Manual: 4WD ECU Malfunction (P163B)

Toyota Tacoma (2015-2018) Service Manual / Differential / Differential System(w/ Rear Differential Lock) / 4WD ECU Malfunction (P163B)

DESCRIPTION

This DTC is output when a malfunction is detected in the 4 wheel drive control ECU internal circuit.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
P163B	4WD ECU Malfunction	Diagnosis Condition: Directly after ignition switch is turned to ON, or when switching operations are performed with ignition switch turned to ON Malfunction Status: 4 wheel drive control ECU internal circuit malfunction Malfunction Time: 0.5 seconds or more (directly after the ignition switch is turned to ON, 0.05 seconds or more) Other: 1 trip detection logic	Wire harness and connector Differential lock coil 4 wheel drive control ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

4WD specification:

If P163B is detected, troubleshoot the TOUCH SELECT 2-4 AND HIGH-LOW system first.

PROCEDURE

1.	CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - DIFFERENTIAL LOCK COIL)

(a) Turn the ignition switch off.

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

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
F12-1 (SL+) - D28-2 (SL+)	Always	Below 1 Ω
F12-5 (SL-) - D28-1 (SL-)	Always	Below 1 Ω
F12-1 (SL+) or D28-2 (SL+) - Body ground	Always	10 kΩ or higher
F12-5 (SL-) or D28-1 (SL-) - Body ground	Always	10 kΩ or higher

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F12-1 (SL+) or D28-2 (SL+) - Body ground	Ignition switch ON	Below 1 V
F12-5 (SL-) or D28-1 (SL-) - Body ground	Ignition switch ON	Below 1 V

REPAIR OR REPLACE HARNESS AND CONNECTOR

2.	INSPECT DIFFERENTIAL LOCK COIL

(a) Turn the ignition switch off.

(b) Disconnect the D28 differential lock coil connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
1 (SL-) - 2 (SL+)	Always	2.65 to 2.95 Ω
1 (SL-) or 2 (SL+) - Body ground	Always	10 kΩ or higher

Text in Illustration

*a	Component without harness connected (Differential Lock Coil)

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
1 (SL-) or 2 (SL+) - Body ground	Ignition switch ON	Below 1 V

REPLACE 4 WHEEL DRIVE CONTROL ECU

REPLACE DIFFERENTIAL LOCK COIL

Rear Differential Lock Position SW Stuck ON (P17BC)

DESCRIPTION This DTC is output when an ON malfunction of the differential lock indicator switch is detected. DTC No. Detection Item DTC Detection Condition ...

ECU Power Source Circuit

WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE: Inspect the fuses for circuits related to this system before performing the following inspection procedure. PROCEDURE 1. ...

Other materials:

Installation
INSTALLATION PROCEDURE 1. INSTALL RADIATOR ASSEMBLY (a) Engage the 2 hooks and temporarily install the radiator assembly to the radiator support sub-assembly. (b) Install the radiator assembly with the 4 bolts. Torque: 18 N·m {184 kgf·cm, 13 ft·lbf} 2. INSTALL FAN SHROUD (a) Install th ...

Open Circuit in IG1/IG2 Power Source Circuit (C1242)
DESCRIPTION If there is a problem with the skid control ECU (master cylinder solenoid) power supply circuit, the skid control ECU outputs the DTC and prohibits operation under the fail safe function. If the voltage supplied to terminal IG1 and/or IG2 is not within the DTC detection threshold ...

Listening to an iPod
Connecting an iPod enables you to enjoy music from the vehicle speakers. Select “iPod” on the “Select Audio Source” screen. When the iPod connected to the system includes iPod video, the system can only output the sound by selecting the browse screen. Connecting an iPod Audio control s ...