Subaru Legacy BN/BS (2015-2019) Service Manual: Inspection
1. WIRING DIAGRAM Refer to “Seat Heater System” in the wiring diagram. • Front: Seat Heater System > WIRING DIAGRAM • Rear: Seat Heater System > WIRING DIAGRAM 2. DIAGNOSTIC CHART
3. CHECK SEAT HEATER FUSE Remove the seat heater fuse, and then visually check. Is the fuse blown out- • Yes > Replace the fuse. • No > Check the power supply and ground circuits. 4. CHECK POWER SUPPLY AND GROUND CIRCUIT 1. Check power supply circuit (1) Disconnect the seat heater control module harness connector. (2) Measure the voltage between harness connector terminal and chassis ground. Connector & terminal (R49) No. 14 (+) — Chassis ground (−): Is the voltage 10 V or more- • Yes > Go to step 2. • No > Repair or replace the harness. 2. Check power supply circuit (1) Turn the ignition switch to ON. (2) Measure the voltage between harness connector terminal and chassis ground. Connector & terminal (R49) No. 5 (+) — Chassis ground (−): Is the voltage 10 V or more- • Yes > Go to step 3. • Repair or replace the harness. 3. Check ground circuit Measure the resistance between harness connector terminal and chassis ground. Connector & terminal (R49) No. 7 — Chassis ground: (R138) No. 9 — Chassis ground: Is the resistance less than 10 -- • Yes > Go to step 4. • No > Repair the harness. 4. Check harness Measure the resistance between seat heater control module terminal and seat heater switch - rear terminal. Connector & terminal (R53) No. 14 — (R138) No. 1: (R53) No. 16 — (R138) No. 6: (R53) No. 6 — (R138) No. 2: (R53) No. 4 — (R138) No. 5: (R53) No. 2 — (R138) No. 13: (R53) No. 8 — (R138) No. 4: Is the resistance less than 10 -- • Yes > Go to step 5. • No > Repair the harness. 5. Check seat heater module (rear) Check the seat heater module (rear) as a single part. Connector & terminal (R49) No. 7 — Chassis ground: (R138) No. 9 — Chassis ground: Is the inspection result normal- • Yes > Replace the seat heater switch - rear or seat heater control module. • No > Replace the seat heater module (rear). 5. SEAT HEATER MODULE (REAR) 1. Disconnect the seat heater unit connector, and check the continuity between terminals of connector.
Connector & terminal Seat cushion: LH side No. 4 — No. 3: Backrest LH: No. 4 — No. 3: Backrest RH: No. 4 — No. 3:
2. If no continuity exists, replace the seat heater module with a new part. 6. CHECK REAR SEAT HEATER SWITCH 1. Remove the rear seat heater switch and measure the resistance between switch terminals. Preparation tool: Circuit tester
NOTE: If the light does not illuminate properly even though the continuity check result is normal, replace the switch. 2. Apply battery voltage between the connector terminals to check lighting condition of illumination inside the switch.
3. Replace the rear seat heater switch if the inspection result is not within the standard value. 7. CHECK REAR SEAT HEATER CONTROL MODULE
1. Disconnect the connector of rear seat heater control module. 2. Check the continuity between the connectors. Connector & terminal 5 — 7 14 — 7 Is there continuity- • Yes > Repair or replace the harness. • No > Replace the rear seat heater control module. | |||||||||||||||||||||||||||||||||||||
Removal
1. SEAT HEATER MODULE - FRONT1. Remove the front seats. Front Seat > REMOVAL2. Remove the backrest cover of front seat and seat cushion cover. Front Seat > DISASSEMBLY3. Remove the seat heater modul ...
Installation
1. SEAT HEATER MODULE - FRONT1. Affix the seat heater module - front to the pad assembly.CAUTION:• If the cover - front cushion is removed, make sure to replace the hang wire on the cover - fron ...
Other materials:
Preparation tool
1. SPECIAL TOOLILLUSTRATIONPart No.DESCRIPTIONREMARKS20099PA010INSTALLER & REMOVER• Used for replacing the bushing - trailing link of the housing assembly - rear axle.• Used together with BUSHING REMOVER (20099FG000).20099FG000BUSHING REMOVER• Used for replacing the bushing - trail ...
