Seat Heater Control Unit Input Test/Replacement
NOTE:
- SRS Components are located in this area. Review the SRS component locations (see COMPONENT LOCATION INDEX ), and precautions and procedures (see PRECAUTIONS AND PROCEDURES ) before doing repairs or servicing.
- Before testing, make sure the No. A3-4 (AS FB-1) (50 A) fuse in the main under-hood fuse box, and the No. C22 (15 A) fuse in the driver's under-dash fuse/relay box are OK.
- Before testing, troubleshoot the multiplex integrated control system first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
- Turn the ignition switch to LOCK (0).
- Remove the passenger's seat (see
FRONT SEAT REMOVAL/INSTALLATION
).NOTE: Be careful not to scratch the interior trim.
- Disconnect the 14P connector (A) from the seat heater control unit (B).
- 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 5.
- Reconnect the 14P connector to the control unit, 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 6.TROUBLESHOOTING CHART
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained 9 LT GRN Ignition switch ON (II) Measure the voltage to ground:
There should be battery voltage.- Blown No. D20 (7.5 A) fuse in the passenger's under-dash fuse/relay box
- An open or high resistance in the wire
2 PNK Ignition switch ON (II) Measure the voltage to ground:
There should be battery voltage.- Blown No. D5 (20 A) fuse in the passenger's under-dash fuse/relay box
- Faulty seat heater relay
- An open or high resistance in the wire
4 BLK In all ignition switch positions Measure the voltage to ground:
There should be less than 0.2 V.- Poor ground (G651)
- An open or high resistance in the ground wire
3 LT BLU Ignition switch ON (II) Measure the voltage to ground:
There should be battery voltage.- Faulty front passenger's seat cushion heater
- An open or high resistance in the wire
1 RED Ignition switch ON (II) Measure the voltage to ground:
There should be battery voltage.- Faulty driver's seat cushion heater
- An open or high resistance in the wire
- Disconnect the 14P connector from the control unit, 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, the control unit must be faulty; replace it.TROUBLESHOOTING CHART
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained 13 WHT Under all conditions Check for continuity between terminal No. 7 and No. 13:
There should be continuity.- Faulty driver's seat cushion heater
- An open or high resistance in the wire
7 PUR 12 BRN Under all conditions Check for continuity between terminal No. 6 and No. 12:
There should be continuity.- Faulty front passenger's seat cushion heater
- An open or high resistance in the wire
6 GRN