Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: Lost Communication with Alternator Missing Message (P161A87)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Power Source & Network / 2gr-fks (battery / 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.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

Note

P161A87

Lost Communication with Alternator Missing Message

Generator assembly or ECM communication stops for approximately 17 minutes or more with the engine switch on (IG).

(1 trip detection logic)
  • Wire harness or connector
  • Generator assembly
  • ECM

Charge warning light comes on

DTC stored

SAE Code: P161A

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.
  • Before replacing the ECM, refer to Service Bulletin.

PROCEDURE

1.

CHECK CHARGING SYSTEM

(a) Check the charging system.

Click here

NG

REPAIR OR REPLACE CHARGING SYSTEM
OK

2.

CHECK HARNESS AND CONNECTOR (ECM - GENERATOR ASSEMBLY)

(a) Disconnect the D2 ECM connector.

(b) Disconnect the D48 generator assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D48-2 (LIN) - D2-135 (LIN)

Always

Below 1 Ω

D48-2 (LIN) or D2-135 (LIN) - Body ground

Always

10 kΩ or higher
OK

REPLACE GENERATOR ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
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    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Owners Manual

    Lexus RX (RX 350L, RX450h) 2016-{YEAR} Repair Manual

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