Front Seat Heater Control Unit Input Test
NOTE:
Make sure the fuses associated with the system is OK.
If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.
Before testing, do the seat heater control unit self-diagnostic function, and make sure the seat heater function is OK.

1.
Turn the vehicle to the OFF (LOCK) mode.

2.
Disconnect the front seat heater control unit 24P connector.
Front Seat Heater Control Unit 24P Connector (female terminals)

3.
Inspect the connector and socket terminals to be sure they are all making good contact:
If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
If the terminals look OK, go to step 4.

4.
Reconnect the front seat heater control unit 24P connector, and do the following input tests:
If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, go to step 5.

Cavity
Wire
Test condition
Test: Desired result
Possible cause if desired result is not obtained
2
PNK
Vehicle ON mode
Measure the voltage to ground:
There should be battery voltage.
Faulty front seat heater relay circuit
An open or high resistance in the wire
14
RED
Vehicle ON mode
Measure the voltage to ground:
There should be battery voltage.
An open or high resistance in the wire
4
PUR
In all power modes
Measure the voltage to ground:
There should be less than 0.2 V.
Poor ground (G402)
An open or high resistance in the ground wire
1
WHT
Vehicle ON mode, driver's seat heater ON mode
Measure the voltage to ground:
There should be battery voltage.
Faulty driver's seat heater
Poor ground (G502) or an open in the ground wire
An open or high resistance in the wire
3
WHT
Vehicle ON mode, front passenger's seat heater ON mode
Measure the voltage to ground:
There should be battery voltage.
Faulty front passenger's seat heater
Poor ground (G502) or an open in the ground wire
An open or high resistance in the wire

5.
Turn the vehicle to the OFF (LOCK) mode.

6.
Disconnect the front seat heater control unit 24P connector, and do the following input tests:
If any test indicates a problem, find and correct the cause, then recheck the system.
If all the input tests prove OK, replace the front seat heater control unit.

Cavity
Wire
Test condition
Test: Desired result
Possible cause if desired result is not obtained
15*
GRN
Disconnect the rear seat heater control unit 24P connector
Check for continuity between terminal No. 15 and rear seat heater control unit 24P connector terminal No. 15:
There should be continuity.
An open or high resistance in the wire
Check for continuity to ground:
There should be no continuity.
A short to ground in the wire
12
LT GRN
Under all conditions
Check for continuity between terminals No. 12 and No. 22:
There should be continuity.
Faulty driver's seat cushion heater
An open or high resistance in the wire
22
BLU
13
PUR
Under all conditions
Check for continuity between terminals No. 13 and No. 23:
There should be continuity.
Faulty front passenger's seat cushion heater
An open or high resistance in the wire
23
LT GRN
*: With rear seat heater