Toyota Tacoma (2015-2018) Service Manual: Lost Communication with Alternator Missing Message (P161A87)

Toyota Tacoma (2015-2018) Service Manual / 2gr-fks Charging / Charging System / Lost Communication with Alternator Missing Message (P161A87)

DESCRIPTION

The ECM communicates with the generator assembly via LIN communication. If a LIN communication error is detected, the ECM stores this DTC.

DTC No.	DTC Detection Condition	Trouble Area
P161A87	Generator assembly or ECM communication stop for about 17 minutes or more with the ignition switch ON. (1 trip detection logic)	Wire harness and connector Generator assembly ECM

DTC No.

DTC Detection Condition

Trouble Area

P161A87

Generator assembly or ECM communication stop for about 17 minutes or more with the ignition switch ON.

(1 trip detection logic)

Wire harness and connector
Generator assembly
ECM

WIRING DIAGRAM

PROCEDURE

1.	CHECK CHARGING SYSTEM

(a) Check the charging system (See page ).

REPAIR OR REPLACE CHARGING SYSTEM

2.	CHECK HARNESS AND CONNECTOR (ECM - GENERATOR ASSEMBLY)

(a) Disconnect the E9 ECM connector.

(b) Disconnect the G2 generator assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
E9-34 (LIN) - G2-2 (LIN)	Always	Below 1 Ω
E9-34 (LIN) or G2-2 (LIN) - Body ground	Always	10 kΩ or higher

REPLACE GENERATOR ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

On-vehicle Inspection

ON-VEHICLE INSPECTION PROCEDURE 1. CHECK BATTERY CONDITION NOTICE: If the battery is weak or if the engine is difficult to start, recharge the battery and perform inspections again before return ...

Charging Failure

PROCEDURE 1. CHECK GENERATOR PULLEY WITH CLUTCH (ON-VEHICLE INSPECTION) (a) Start the engine and visually check if the fan of the generator rotor assembly located i ...

Other materials:

Check For Intermittent Problems
CHECK FOR INTERMITTENT PROBLEMS HINT: Inspect the vehicle ECM using check mode. Intermittent problems are easier to detect with the Techstream when the ECM is in check mode. In check mode, the ECM uses 1 trip detection logic, which is more sensitive to malfunctions than normal mode (default) ...

Inspection
INSPECTION PROCEDURE 1. INSPECT AUTO HIGH BEAM SWITCH *a Component without harness connected (Auto High Beam Switch) (a) Check the resistance. (1) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester C ...

Data List / Active Test
DATA LIST / ACTIVE TEST 1. DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals ...