B1491

AIR CONDITIONING: AIR CONDITIONING SYSTEM: B1491/91: HV Battery Cool Down Servo Motor Circuit

DTC B1491/91 - HV Battery Cool Down Servo Motor Circuit

DESCRIPTION

The HV battery cool down servo sends pulse signals to inform the air conditioning amplifier of the damper position. The air conditioning amplifier activates the motor (normal or reverse) based on these signals to move the HV battery cool down servo motor to the appropriate position, which controls the HV battery cool down modes.
HINT: Confirm that no mechanical problem is present because this diagnostic code can be output when either a damper link or damper is mechanically locked.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING INTELLIGENT TESTER OR TECHSTREAM (BATTERY COOL DOWN SERVO MOTOR TARGET PULSE)
(a) Use the Data List to check if the servo motor is functioning properly.
(1) Intelligent tester

AIR CONDITIONER

(2) Techstream

Air conditioner

OK:
The display is as specified in the normal condition.
NG -- CHECK HARNESS AND CONNECTOR (REAR AIR CONDITIONING HARNESS - AIR CONDITIONING AMPLIFIER)
OK -- REPLACE AIR CONDITIONING AMPLIFIER
2. CHECK HARNESS AND CONNECTOR (REAR AIR CONDITIONING HARNESS - AIR CONDITIONING AMPLIFIER)

(a) Disconnect the S28 rear air conditioning harness connector.
(b) Disconnect the L76 air conditioning amplifier connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. REPLACE HV BATTERY COOL DOWN SERVO MOTOR
(a) Replace the HV battery cool down servo motor Disassembly.
HINT: Since the servo motor cannot be inspected while it is removed from the vehicle, replace the servo motor with a normal one.

NEXT -- Continue to next step.
4. RECHECK DTC
(a) Clear the DTCs DTC Check / Clear.
(b) Check for DTCs DTC Check / Clear.
OK:
DTC B1491 is not output.
NG -- REPLACE REAR AIR CONDITIONING HARNESS
OK -- END (HV BATTERY COOL DOWN SERVO MOTOR IS DEFECTIVE)