Front Seat Heater Control Unit Input Test

NOTE:

Make sure the fuses associated with the system are 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)

Courtesy of HONDA, U.S.A., INC.

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.

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	PUR* 1RED* 2	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

*1: With auto idle stop system

*2: Without auto idle stop system

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
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

*1: With auto idle stop system

*2: Without auto idle stop system

5. Turn the vehicle to the OFF (LOCK) mode. 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
15*	GRN	Disconnect the rear seat heater control unit 24P connector	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	Under all conditions
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	Under all conditions

*: With rear seat heater