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Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Heating / Air Conditioning System (Except HV, W/ Auto A/C) - Diagnostic Codes (1 Of 2) >> AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System) >> DTC B142A-88: Servo Motor LIN Communication Bus off [11/2023 - ] >> Description

DTC B142A-88: Servo Motor LIN Communication Bus off [11/2023 - ]: Description

The air conditioning harness assembly connects the air conditioning amplifier assembly and the servo motors.

The air conditioning amplifier assembly supplies power and sends operation instructions to each servo motor through the air conditioning harness assembly.

Each servo motor sends damper position information to the air conditioning amplifier assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory DTC Output from Priority
B142A-88 Servo Motor LIN Communication Bus off Diagnosis Condition:
  1. Ignition switch ON

Malfunction:

  1. Error or open in communication line between air conditioning amplifier assembly and each servo motor

Detection Time:

  1. Continuously for 10 seconds or more
  • Air conditioning harness assembly
  • No. 1 air conditioning radiator damper servo sub-assembly
  • Air conditioning amplifier assembly
Memorized Air Conditioner A
DTC DETECTION CONDITION COMBINATION TABLE

  Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition Ignition switch ON
Malfunction Error in communication line between air conditioning amplifier assembly and each servo motor -
Open in communication line between air conditioning amplifier assembly and each servo motor -
Detection Time Continuously for 10 seconds or more Continuously for 10 seconds or more
Trip Count 1 trip 1 trip

HINT: 

If the conditions of either of these patterns are detected, a DTC will be stored.