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Front Seat Heater Control Unit Input Test

NOTE:  Before testing, make sure the No. B5 (10 A), No. B9 (10 A), and No. B32 (20 A) fuses in the under-dash fuse/relay box are OK.

1. Disconnect the front seat heater control unit 14P connector .

GHH411278Courtesy of HONDA, U.S.A., INC.

Inspect the connector and socket terminals to be sure they are all making good contact:

With the connector still disconnected, do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
13*7 ORN*YEL Under all conditions Check for continuity between terminals No. 13 and No. 7: There should be continuity.
  • Faulty driver's seat cushion heater
  • An open or high resistance in the wire
12*6 GRN*BLU Under all conditions Check for continuity between terminals No. 12 and No. 6: There should be continuity.
  • Faulty front passenger's seat cushion heater
  • An open or high resistance in the wire

Reconnect the connector, and do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
2 LT GRN Vehicle ON mode Measure the voltage to ground: There should be battery voltage.
  • Blown No. B32 (20 A) fuse in the under-dash fuse/relay box
  • Faulty front seat heater relay circuit
  • An open or high resistance in the wire
9 RED Vehicle ON mode Measure the voltage to ground: There should be battery voltage.
  • Blown No. B5 (10 A) fuse in the under-dash fuse/relay box
  • An open or high resistance in the wire
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
4 BLK In all power modes Measure the voltage to ground: There should be less than 0.2 V.
  • Poor ground (G602)
  • An open or high resistance in the ground wire
1 GRN Vehicle ON mode, driver's seat heater operation Measure the voltage to ground: There should be battery voltage.
  • Faulty driver's seat heater
  • Poor ground (G601) or an open in the ground wire
  • An open or high resistance in the wire
3 RED Vehicle ON mode, front passenger's seat heater operation Measure the voltage to ground: There should be battery voltage.
  • Faulty front passenger's seat heater
  • Poor ground (G602) or an open in the ground wire
  • An open or high resistance in the wire