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Rear Heater Control Panel LIN Communication Malfunction








MULTIPLEX COMMUNICATION: LIN COMMUNICATION SYSTEM: Rear Heater Control Panel LIN Communication Malfunction

Rear Heater Control Panel LIN Communication Malfunction

DESCRIPTION

The LIN communication of the components related to the rear heater occurs between the air conditioning amplifier (A/C ECU) and rear power seat module switch.

WIRING DIAGRAM





INSPECTION PROCEDURE
NOTICE:
When using the Techstream with the power switch OFF to troubleshoot:

Connect the Techstream to the vehicle, and turn a courtesy switch on and off at 1.5 second intervals until communication between the tester and vehicle begins.

PROCEDURE

1.
CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - REAR POWER SEAT MODULE SWITCH)




(a) Disconnect the L76 amplifier connector.
(b) Disconnect the z54*1 or S15*2 module switch connector.
(c) Measure the resistance and voltage according to the value(s) in the table below.
Standard resistance:

except Ottoman:





for Ottoman:





Standard voltage:

except Ottoman:





for Ottoman:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
2. CHECK HARNESS AND CONNECTOR (REAR POWER SEAT MODULE SWITCH - BATTERY AND BODY GROUND)




(a) Disconnect the z54*1 or S15*2 module switch connector.
(b) Measure the resistance and voltage according to the value(s) in the table below.
Standard resistance:

except Ottoman:





for Ottoman:





Standard voltage:

except Ottoman:





for Ottoman:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
3. CHECK REAR POWER SEAT MODULE SWITCH (OPERATION)
(a) Temporarily replace the rear power seat module switch with a new or normally functioning one Disassembly.
(b) Check the rear air conditioning function is normal.
OK:
Rear air conditioning function is normal.
NG -- REPLACE AIR CONDITIONING AMPLIFIER
OK -- END (REAR POWER SEAT MODULE SWITCH IS DEFECTIVE)