Body Control Systems: Other Lexus LS III

CIRCUIT TESTS

Note. Perform circuit tests in order listed in appropriate SYMPTOM DIAGNOSIS table under TROUBLE SHOOTING . If LEXUS scan tool is available for the following circuit tests, connect scan tool to Data Link Connector 3 (DLC3) located under left side of instrument panel.

BACK-UP LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate back-up lights in ACTIVE TEST. If back-up lights do not operate, go to next step. If back-up lights operate, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check back-up light bulbs. Replace bulbs as necessary. If bulbs are okay, check circuits for faults between back-up lights, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

BODY NO. 2 ECU POWER SOURCE CIRCUIT

1. Check MPX-B3, MPX-IG, D B/ANC, HAZ and PANEL fuses. See «FUSE LOCATIONS (BODY NO. 2 ECU)»(ref-27018-S03319979922001022800000) table. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
2. Turn ignition on. Measure voltage between driver-side junction block terminals MPX-IG and GND. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . Voltage should be 10-14 volts. Turn ignition off. Disconnect driver-side junction block connector. Measure voltage between driver-side junction block connector terminal GND2 and terminals MPXB, A/ANC, HAZ and PANEL1. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If 10-14 volts are not present, check wiring between body No. 2 ECU and ground. Repair wiring as necessary. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . If wiring is okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

FUSE LOCATIONS (BODY NO. 2 ECU)

BODY NO. 3 ECU POWER SOURCE CIRCUIT

1. Check condition of MPX-IG, MPX-B1, WIP and P B/ANC fuses. See «FUSE LOCATIONS (BODY NO. 3 ECU)»(ref-27018-S17363040892001022800000) table. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
2. Turn ignition on. Measure voltage between passenger-side junction block terminal GND and terminals MPX-IG and ACC. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . Turn ignition off. Disconnect passenger-side junction block connector. Measure voltage between passenger-side junction block connector terminal GND and terminals MPX-B, WIP and P B/ANC. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If 10-14 volts are not present, check wiring between body No. 3 ECU and ground. Repair wiring as necessary. If wiring is okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

FUSE LOCATIONS (BODY NO. 3 ECU)

BODY NO. 4 ECU POWER SOURCE CIRCUIT

1. Check condition of MPX-B3 and LUG J/B fuses. See «FUSE LOCATIONS (BODY NO. 4 ECU)»(ref-27018-S20467788582001030200000) table. If fuses are okay, go to next step. If fuse(s) are faulty, replace appropriate fuse and retest system operation.
2. Disconnect body No. 4 ECU connector. Measure voltage between body No. 4 ECU connector terminal GND and terminals MPX-B and HIC. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . Turn ignition off. If 10-14 volts are not present, go to next step. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
3. Check wiring between body No. 4 ECU and ground. Repair wiring as necessary. If wiring is okay, check wiring between body No. 4 ECU and battery. Repair as necessary.

FUSE LOCATIONS (BODY NO. 4 ECU)

BODY NO. 5 ECU POWER SOURCE CIRCUIT

1. Check MPX-B3 fuse located in passenger-side junction block. Replace fuse as necessary. If fuse is okay, go to next step. If fuse is faulty, replace appropriate fuse and retest system operation.
2. Ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between body No. 5 ECU connector terminals No. 29 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If 10-14 volts are not present, go to next step. If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
3. Check wiring between body No. 5 ECU and ground. Repair wiring as necessary. If wiring is okay, check wiring between body No. 5 ECU and battery. Repair as necessary.

BRAKE PAD INDICATOR SENSOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check brake pad sensor circuit using DATA LIST. If brake pad sensor is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If brake pad sensor is not okay, go to next step.
2. Disconnect brake pad sensor wear indicator 2-pin connector. Check continuity between connector terminals. If continuity is present, sensor is okay. Go to next step. If continuity is not present, replace sensor.
3. Check circuits for faults between brake pad sensor wear indicator and body No. 3 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

DRIVER SEAT BELT BUCKLE ILLUMINATION CIRCUIT

Check driver buckle illumination. See WIRING DIAGRAMS . Replace bulb or repair circuit as necessary. If circuits are okay, go to next test listed in BODY NO. 2 CONTROL SYSTEM table under TROUBLE SHOOTING .

DRIVER SEAT BELT BUCKLE SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check driver seat belt buckle switch using DATA LIST. If driver seat belt buckle switch is faulty, go to next step. If driver seat belt buckle switch is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check driver seat belt buckle switch. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Replace driver seat belt buckle switch as necessary. Retest system operation. If driver seat belt buckle switch is okay, go to next step.
3. Check circuits for faults between driver seat belt buckle switch, body control ECU and ground. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

DRIVER SEAT BELT TENSION REDUCER CIRCUIT

Check seat belt tension reducer switch. See WIRING DIAGRAMS . Replace switch as necessary. If switch is okay, check wiring between switch and driver-side junction block ECU. Repair wiring as necessary. If wiring is okay, go to next test listed in BODY NO. 2 CONTROL SYSTEM table under TROUBLE SHOOTING .

DOOR COURTESY SWITCH SIGNAL CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check door courtesy switch signal using ACTIVE TEST. If door courtesy switch is faulty, go to next step. If door courtesy switch is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check door courtesy light bulb. Replace as necessary. If bulb is okay, check circuits for faults between door courtesy switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

ELECTRONICALLY CONTROLLED TRANSMISSION (ECT) PATTERN SELECT SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check pattern select switch using DATA LIST. If pattern select switch is faulty, go to next step. If pattern select switch is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check pattern select switch. See «PATTERN SELECT SWITCH»(ref-27018-S06811420872001030900000) under COMPONENT TESTS. Replace pattern select switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between pattern select switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

ENGINE HOOD COURTESY SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check engine hood courtesy switch using DATA LIST. If engine hood courtesy switch is faulty, go to next step. If engine hood courtesy switch is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check engine hood courtesy switch. See «ENGINE HOOD COURTESY SWITCH»(ref-27018-S24403182412001010800000) under COMPONENT TESTS. Replace engine hood courtesy switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between engine hood courtesy switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

FOG LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate fog lights in ACTIVE TEST. If fog lights do not operate, go to next step. If fog lights operate, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000).
2. Check FR FOG fuse located in engine room junction block. Replace fuse as necessary. If fuse is okay, ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between connector terminals No. 3 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000). If 10-14 volts are present, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000). If 10-14 volts are not present, check foglights. Replace foglights as necessary. If foglights are okay, check foglight relay. (Scheme 7) If foglight relay is okay, check circuits for faults between foglight, body No. 5 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000). Repair or replace as necessary.

Scheme 7

FUEL LID OPENER MOTOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check fuel lid opener motor using ACTIVE TEST. If fuel lid opener motor is faulty, go to next step. If fuel lid opener motor is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check FUEL OPN fuse located in luggage room junction block. Replace fuse as necessary. If fuse is okay, check fuel lid opener motor. See «FUEL LID OPENER MOTOR»(ref-27018-S19700205072001031200000) under COMPONENT TESTS. Replace fuel lid opener motor as necessary. If fuel lid opener motor is okay, go to next step.
3. Check circuits for faults between fuel lid opener motor and body No. 4 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

FUEL LID OPENER SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check fuel lid opener switch using DATA LIST. If fuel lid opener switch is faulty, go to next step. If fuel lid opener switch is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check fuel lid opener switch. See «FUEL LID OPENER SWITCH»(ref-27018-S20608318062001030900000) under COMPONENT TESTS. Replace fuel lid opener switch as necessary. If fuel lid opener switch is okay, go to next step.
3. Check circuits for faults between fuel lid opener switch and body No. 2 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

FUEL SENDER MAIN & SUB GAUGE CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check fuel sender main and sub gauge using DATA LIST. If fuel sender main and sub gauge are faulty, go to next step. If fuel sender main and sub gauge are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check fuel sender main gauge. See FUEL GAUGE in INSTRUMENT PANELS - LS430 article. Replace fuel sender main gauge as necessary. If fuel sender main gauge is okay, go to next step.
3. Check wiring and connectors between fuel sender main gauge and body No. 4 ECU. Repair wiring as necessary. If wiring is okay, check fuel sender sub gauge. See FUEL GAUGE in INSTRUMENT PANELS - LS430 article. Replace fuel sender sub gauge as necessary. If fuel sender sub gauge is okay, check wiring and connectors between fuel sender sub gauge and body No. 4 ECU. Repair wiring as necessary. If wiring is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

HAZARD SWITCH CIRCUIT

1. Check hazard switch. See «HAZARD SWITCH»(ref-27018-S39658020692001010800000) under COMPONENT TESTS. Replace hazard switch as necessary. Retest system operation. If hazard switch is okay, go to next step.
2. Check circuits for faults between hazard switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

HEADLIGHT BEAM LEVEL CONTROL ECU COMMUNICATION CIRCUIT

Check headlight beam level control ECU. See HEADLIGHT BEAM LEVEL CONTROL ECU under COMPONENT TESTS. If headlight beam level control ECU is okay, check wiring between headlight beam level control ECU and passenger-side junction block. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, go to next test listed in BODY NO. 2 CONTROL SYSTEM table under TROUBLE SHOOTING .

HEADLIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate headlight in ACTIVE TEST. If headlight does not operate, go to next step. If headlight operates, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check H-LP HI fuse located in engine room junction block. Replace fuse as necessary. If fuse is okay, ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between connector terminals No. 12 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If 10-14 volts are present, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If 10-14 volts are not present, check headlight bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between headlights, body No. 5 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary.

HEADLIGHT CLEANER SWITCH CIRCUIT

Check headlight cleaner switch. See HEADLIGHT CLEANER SWITCH under COMPONENT TESTS. Replace switch as necessary. If switch is okay, check wiring between switch and driver-side junction block ECU. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, go to BODY NO. 2 CONTROL SYSTEM table under TROUBLE SHOOTING .

HEADLIGHT RELAY CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate headlight relay in ACTIVE TEST. If headlight relay does not operate (headlights do not illuminate), go to next step. If headlight relay operates (headlights illuminate), go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check headlight relay. See «HEADLIGHT RELAY»(ref-27018-S09740208572001010800000) under COMPONENT TESTS. Replace headlight relay as necessary. Retest system operation. If headlight relay is okay, go to next step.
3. Check circuits for faults between headlight relay, body control ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

HIGH-MOUNTED STOPLIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate high-mounted stoplight using ACTIVE TEST. If high-mounted stoplight does not operate, go to next step. If high-mounted stoplight operates, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between high-mounted stoplight, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

HORN CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate horn in ACTIVE LIST. If horn does not operate, go to next step. If horn operates, go to next test listed in «BODY NO. 5 CONTROL SYSTEM»(ref-27018-S09945925742001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check HORN fuse located in engine room junction block. Replace fuse as necessary. If fuse is okay, go to next step.
3. Ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between connector terminals No. 15 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If voltage is 10-14 volts, go to next test listed in «BODY NO. 5 CONTROL SYSTEM»(ref-27018-S09945925742001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If voltage is not 10-14 volts, apply battery voltage directly to horn. If horn does not sound, replace horn. If horn sounds, check circuits for faults between horn and body No. 5 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay

IGNITION SWITCH POWER SOURCE CIRCUIT (BODY NO. 4 ECU)

1. Check D/C CUT and RR ACC fuses located in luggage compartment junction block. Replace as necessary. If fuses are okay, ensure ignition is off. Disconnect luggage room junction block (body No. 4 ECU) connector. Measure voltage between terminal GND and terminals MPX-IG and ACC. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If 10-14 volts are not present, go to next step. If 10-14 volts are present, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check wiring and connectors between body No. 4 ECU and ground. Repair circuit as necessary. If wiring is okay, check wiring and connectors between body No. 4 ECU and battery. Repair circuit as necessary.

IGNITION SWITCH POWER SOURCE CIRCUIT (BODY NO. 5 ECU)

1. Check MPX-IG fuse and D-IG1 relay located in driver-side junction block. Replace fuse or relay as necessary. If fuse and relay are okay, turn ignition on. Measure voltage between body No. 5 ECU connector terminals No. 30 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If 10-14 volts are not present, go to next step. If 10-14 volts are present, go to next test listed in «BODY NO. 5 CONTROL SYSTEM»(ref-27018-S09945925742001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check wiring and connectors between body No. 5 ECU and ground. Repair circuit as necessary. If wiring is okay, check wiring and connectors between body No. 5 ECU and battery. Repair circuit as necessary.

INSTRUMENT CLUSTER CIRCUIT

Check instrument cluster circuit. See INSTRUMENT PANELS - LS430 article. Replace cluster as necessary. If cluster is okay, check circuit for faults between cluster and body No. 2 ECU. See WIRING DIAGRAMS . Repair or replace as necessary.

LICENSE PLATE LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate license plate light in ACTIVE TEST. If license plate light does not operate, go to next step. If license plate light operates, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check license plate bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between license plate light, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT DOOR CLOSER SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check luggage compartment door closer switch using DATA LIST. If luggage compartment door closer switch is faulty, go to next step. If luggage compartment door closer switch is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check luggage compartment door closer switch. See «LUGGAGE COMPARTMENT DOOR CLOSER SWITCH»(ref-27018-S27272562592001031200000) under COMPONENT TESTS. Replace luggage compartment door closer switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between luggage compartment door closer switch and body No. 4 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT DOOR COURTESY SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check luggage compartment door courtesy switch using DATA LIST. If luggage compartment door courtesy switch is faulty, go to next step. If luggage compartment door courtesy switch is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check luggage compartment door courtesy switch. See «LUGGAGE COMPARTMENT DOOR COURTESY SWITCH»(ref-27018-S07359276302001010800000) under COMPONENT TESTS. Replace luggage compartment door courtesy switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between luggage compartment door courtesy switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT DOOR KEY LOCK & UNLOCK SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check luggage compartment door key lock and unlock switch using DATA LIST. If luggage compartment door key lock and unlock switch is faulty, go to next step. If luggage compartment door key lock and unlock switch is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check luggage compartment door key lock and unlock switch. See «LUGGAGE COMPARTMENT DOOR KEY LOCK & UNLOCK SWITCH»(ref-27018-S04304475112001010800000) under COMPONENT TESTS. Replace switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between luggage compartment door key lock and unlock switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT DOOR OPENER MOTOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate luggage compartment opener motor in ACTIVE TEST. If luggage compartment opener motor does not operate, go to next step. If luggage compartment opener motor operates properly, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check FUEL OPN fuse in luggage compartment junction block. Replace fuse as necessary. If fuse is okay, check luggage compartment opener motor. See «LUGGAGE COMPARTMENT DOOR OPENER MOTOR»(ref-27018-S40391205012001010800000) under COMPONENT TESTS. Replace luggage compartment opener motor as necessary. Retest system operation. If motor is okay, go to next step.
3. Check circuits for faults between luggage compartment opener motor and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT DOOR OPENER SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check luggage compartment opener switch using DATA LIST. If luggage compartment opener switch is faulty, go to next step. If luggage compartment opener switch is okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check luggage compartment main switch and opener switch. See «LUGGAGE COMPARTMENT DOOR OPENER SWITCH»(ref-27018-S02690268342001010800000) under COMPONENT TESTS. Replace luggage compartment switch as necessary. Retest system operation. If switch is okay, go to next step.
3. Check circuits for faults between luggage compartment opener switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

LUGGAGE COMPARTMENT LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate luggage compartment light in ACTIVE TEST. If luggage compartment light does not operate, go to next step. If luggage compartment light operates, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check RR ECU-B fuse located in luggage compartment junction block. Replace fuse as necessary. If fuse is okay, check luggage compartment bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between luggage compartment light, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

NAVIGATION ECU COMMUNICATION CIRCUIT

Check wiring between body No. 3 ECU and navigation ECU. See WIRING DIAGRAMS . Repair wiring as necessary. If wiring is okay, replace navigation ECU with a known-good unit. If navigation ECU and circuits are okay, go to next test listed in BODY NO. 3 CONTROL SYSTEM table under TROUBLE SHOOTING .

PARKING LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate parking light in ACTIVE TEST. If parking light does not operate, go to next step. If parking light operates, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check TAIL fuse located in engine room junction block. Replace fuse as necessary. If fuse is okay, ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between connector terminals No. 9 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If 10-14 volts are present, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If 10-14 volts are not present, check parking light bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between parking lights, body No. 5 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary.

PASSENGER SEAT BELT BUCKLE ILLUMINATION CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check passenger seat belt buckle illumination using ACTIVE TEST. If passenger seat belt buckle illumination is faulty, go to next step. If passenger seat belt buckle illumination is okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check passenger buckle illumination. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If buckle illumination is okay, check wiring between buckle illumination and body No. 3 ECU. Repair wiring as necessary.

PASSENGER SEAT BELT TENSION REDUCER CIRCUIT

Check passenger buckle tension reducer solenoid. See SEAT BELT TENSION REDUCER SOLENOID under CIRCUIT TESTS. If solenoid is okay, check circuits for faults between buckle tension reducer and body No. 3 ECU. Repair or replace as necessary. See WIRING DIAGRAMS . If circuits are okay, go to next test listed in BODY NO. 3 CONTROL SYSTEM table under TROUBLE SHOOTING .

REAR A/C AMPLIFIER CIRCUIT

Check wiring and connectors between rear A/C amplifier and body No. 4 ECU. See WIRING DIAGRAMS . Repair wiring and connectors as necessary. If wiring and connector are okay, go to next test listed in BODY NO. 4 CONTROL SYSTEM table under TROUBLE SHOOTING .

REAR SEAT BELT BUCKLE ILLUMINATION CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate rear seat belt buckle light in ACTIVE TEST. If rear seat belt buckle light does not operate, go to next step. If rear seat belt buckle light operates, go to next test listed in «BODY NO. 4 CONTROL SYSTEM»(ref-27018-S19036109972001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check rear seat belt buckle light. Replace buckle as necessary. If buckle light is okay, check circuits for faults between seat belt buckle light, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

REAR SEAT RETURN SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check rear seat return switch function using DATA LIST. If switch is okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If switch is not okay, go to next step.
2. Check rear seat return switch. See «REAR SEAT RETURN SWITCH»(ref-27018-S09310045772001031200000) under COMPONENT TESTS. Replace switch as necessary. If switch is okay, go to next step.
3. Check circuits for faults between rear seat return switch and body No. 3 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

REAR SUNSHADE RELAY COMMUNICATION CIRCUIT

Check rear sunshade switch and relay. See REAR SUNSHADE SWITCH & RELAY under COMPONENT TESTS. Replace as necessary. If rear sunshade switch and/or relay are okay, check wiring between rear sunshade switch, relay and body No. 3 ECU. See WIRING DIAGRAMS . Repair or replace as necessary. If circuits are okay, go to next test listed in BODY NO. 3 CONTROL SYSTEM table under TROUBLE SHOOTING .

RHEOSTAT LIGHT CONTROL CIRCUIT & TAIL SWITCH CANCEL

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check rheostat light control. Value of illumination rate should change in 0-100 range when rheostat light control is illuminated or covered. Using DATA LIST, check tail switch cancel function. If components are okay, go to next step. If components are not okay, replace rheostat light control volume.
2. Check rheostat light control volume. See LIGHT RHEOSTAT CONTROL in INSTRUMENT PANELS - LS430 article. Replace rheostat light control volume as necessary. If rheostat light control volume is okay, go to next step.
3. Check circuits for faults between rheostat light control volume and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

SHOULDER BELT ANCHOR MOTOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, in ACTIVE LIST, check shoulder belt anchor motor. See «SHOULDER BELT ANCHOR MOTOR & SENSOR»(ref-27018-S03704040932001030900000) under COMPONENT TESTS. If anchor motor is okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If anchor motor is not okay, go to next step.
2. Check circuits for faults between shoulder belt anchor motor and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

SHOULDER BELT ANCHOR SENSOR CIRCUIT

1. Check shoulder belt anchor sensor. See «SHOULDER BELT ANCHOR MOTOR & SENSOR»(ref-27018-S03704040932001030900000) under COMPONENT TESTS. Replace shoulder belt anchor sensor as necessary. Retest system operation. If shoulder belt anchor sensor is okay, go to next step.
2. Check circuits for faults between shoulder belt anchor sensor, body control ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

SIDE MARKER LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate side marker lights in ACTIVE TEST. If side marker lights do not operate, go to next step. If side marker lights operate, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check side marker lights. Replace side marker lights as necessary. If side marker lights are okay, check circuits for faults between side marker lights, body No. 5 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . If side marker lights are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

STOPLIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check stoplight circuit using ACTIVE TEST. If stoplight circuit is faulty, go to next step. If stoplight circuit is okay, go to next test listed in appropriate SYMPTOM DIAGNOSIS table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check stoplight bulb. Replace stoplight bulb as necessary. If stoplight bulb is okay, check circuits for faults between stoplight, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

STOPLIGHT SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check stoplight switch using DATA LIST. If stoplight switch is faulty, go to next step. If stoplight switch is okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check stoplight switch. See «STOPLIGHT SWITCH»(ref-27018-S36259453712001010800000) under COMPONENT TESTS. Replace stoplight switch as necessary. Retest system operation. If stoplight switch is okay, go to next step.
3. Check circuits for faults between stoplight switch, body control ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

TAILLIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate taillights in ACTIVE TEST. If taillights do not operate, go to next step. If taillights operate, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check taillight bulb. Replace bulb as necessary. If bulb is okay, check circuits for faults between taillights, body No. 4 ECU and battery. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

TURN SIGNAL LIGHT CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate turn signal light in ACTIVE TEST. If turn signals do not operate, go to next step. If turn signals operate, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check turn signal bulbs. Replace bulbs as necessary. If bulbs are okay, check circuits for faults between turn signal bulbs and body No. 2 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 2 CONTROL SYSTEM»(ref-27018-S35253316762001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

WASHER MOTOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate washer motor in ACTIVE LIST. If washer motor does not operate, go to next step. If washer motor operates, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check WASH fuse located in engine room junction block. Replace fuse as necessary. If fuse is okay, go to next step.
3. Ensure ignition is off. Disconnect body No. 5 ECU connector. Measure voltage between connector terminals No. 4 and 25. See «PIN VOLTAGE TESTS»(ref-27018-S28235275902001031400000) . If voltage is 10-14 volts, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) . If voltage is not 10-14 volts, check washer motor. See WASHER MOTOR in WIPER/WASHER SYSTEMS - LS430 article. Replace washer motor as necessary. If washer motor is okay, check circuits for faults between washer motor and body No. 5 ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay

WIPER/WASHER SWITCH CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, check wiper/washer switch using DATA LIST. If wiper/washer switch is faulty, go to next step. If wiper/washer switch is okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check wiper/washer switch. See WIPER/WASHER SYSTEMS - LS430 article. Replace wiper/washer switch as necessary. Retest system operation. If wiper/washer switch is okay, go to next step.
3. Check circuits for faults between wiper/washer switch and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

WIPER MOTOR CIRCUIT

Note. If LEXUS scan tool is available, start test from step 1 . If this scan tool is not available, start test from step 2 .

1. Using scan tool, operate wiper motor in ACTIVE TEST. If wiper motor does not operate, go to next step. If wiper motor operates, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .
2. Check wiper motor. See WIPER/WASHER SYSTEMS - LS430 article. Replace wiper motor as necessary. Retest system operation. If wiper motor is okay, go to next step.
3. Check circuits for faults between wiper motor and body control ECU. See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000) . Repair or replace as necessary. If circuits are okay, go to next test listed in «BODY NO. 3 CONTROL SYSTEM»(ref-27018-S00966519082001022100000) table under «TROUBLE SHOOTING»(ref-27018-S24130041722001010800000) .

ENGINE HOOD COURTESY SWITCH

Remove engine hood courtesy switch. Check continuity between 2 terminals of engine hood courtesy switch. Continuity should exist with switch pin released. Continuity should not exist with switch pin pressed. If continuity is not as specified, replace courtesy switch and retest system operation.

FUEL LID OPENER MOTOR

Disconnect fuel lid opener motor 2-pin connector. Connect positive battery voltage to terminal No. 2 and negative battery voltage to terminal No. 1. Motor should operate in open direction. (Scheme 8) If operation is not as specified, replace motor.

Scheme 8

FUEL LID OPENER SWITCH

Disconnect fuel lid opener switch 2-pin connector. With switch on, continuity should exist between switch terminals. With switch off, no continuity should exist between switch terminals. Replace switch as necessary.

HAZARD SWITCH

Remove and test hazard switch. See HAZARD SWITCH CONTINUITY TEST table. (Scheme 9) If continuity is not as specified, replace hazard switch and retest system operation.

HAZARD SWITCH CONTINUITY TEST

Scheme 9

HEADLIGHT BEAM LEVEL CONTROL ECU

Turn ignition off. Disconnect headlight beam level control ECU 26-pin connector. (Scheme 10) Check resistance at connector wire on harness side. See HEADLIGHT BEAM LEVEL CONTROL ECU RESISTANCE CHECK. If resistances are not to specification, replace headlight beam level control ECU.

HEADLIGHT BEAM LEVEL CONTROL ECU RESISTANCE CHECK

Scheme 10

HEADLIGHT CLEANER SWITCH

Disconnect headlight cleaner switch 22-pin connector. With switch off, no continuity should be present between any connector terminals. With switch on, continuity should be present between connector terminals No. 10 and 11. (Scheme 11) If continuity is not as specified, replace switch.

Scheme 11

HEADLIGHT RELAY

Remove headlight relay (located in junction block, on left side of engine compartment, in front of shock tower). Check continuity between relay terminals. Continuity should exist between terminals No. 1 and 2. Apply battery voltage and ground between terminals No. 1 and 2. Continuity should exist between terminals No. 3 and 4. (Scheme 7) If continuity is not as specified, replace headlight relay and retest system operation.

LUGGAGE COMPARTMENT DOOR CLOSER SWITCH

Disconnect luggage compartment door closer switch 6-pin connector. With switch off, no continuity should be present between any switch terminals. With switch on, continuity should be present between switch terminals No. 3 and 4. (Scheme 12) Replace switch as necessary.

Scheme 12

LUGGAGE COMPARTMENT DOOR COURTESY SWITCH

Remove luggage compartment door courtesy switch. Check continuity between luggage compartment door courtesy switch terminals. Continuity should exist with switch pin released. Continuity should not exist with switch pin pressed. If continuity is not as specified, replace courtesy switch and retest system operation.

LUGGAGE COMPARTMENT DOOR KEY LOCK & UNLOCK SWITCH

Remove luggage compartment door key lock and unlock switch. Check continuity between luggage compartment door key lock and unlock switch terminals. Continuity should exist with switch in unlock position (key turned in lock). Continuity should not exist with switch in neutral position (key not turned in lock). If continuity is not as specified, replace key lock and unlock switch and retest system operation.

LUGGAGE COMPARTMENT DOOR OPENER MOTOR

Open luggage compartment door. Disconnect 6-pin electrical connector from door opener motor. Connect positive battery lead to door opener motor connector (component side) terminal No. 6 and negative battery lead to door opener motor connector terminal No. 2. Door opener motor should operate to open position. Reverse polarity. Door should operate to close position. (Scheme 13) Replace door opener motor as necessary and retest system operation.

Scheme 13

LUGGAGE COMPARTMENT DOOR OPENER SWITCH

1. Remove luggage compartment door opener switch assembly from lower left side of instrument panel. Check continuity between luggage compartment door opener switch terminals No. 1 and 2. (Scheme 14) See «WIRING DIAGRAMS»(ref-27018-S12483968262001010800000). Continuity should exist with switch on (switch pushed and key turned). Continuity should not exist with switch off (switch pushed and key not turned). If continuity is not as specified, replace door opener switch assembly and retest system operation. If continuity is as specified, go to next step.
2. Check continuity between luggage compartment door opener switch terminal No. 2 and door opener switch terminal "B". (Scheme 14) Continuity should exist with switch off (switch not pulled) and with switch on (switch pulled). Check continuity between luggage compartment door opener switch terminal No. 1 and door opener switch terminal "L". Continuity should only exist with switch on (switch pulled). If continuity is not as specified, replace door opener switch assembly and retest system operation.

Scheme 14

PATTERN SELECT SWITCH

Disconnect pattern select switch connector. (Scheme 15) Check continuity between switch terminals with switch at specified positions. See PATTERN SELECT SWITCH TEST table. Replace switch if continuity is not to specification.

Scheme 15

PATTERN SELECT SWITCH TEST

REAR SEAT RETURN SWITCH

Disconnect rear seat return switch 22-pin connector. Turn switch on. Ensure continuity is present between switch terminals No. 6 and 9. (Scheme 11) If continuity is not present, replace switch.

Scheme 16

1. Disconnect rear seat control rear sunshade switch 3-pin connector at rear seat control. (Scheme 16) With switch off, no continuity should be present between any switch terminal. With switch on, continuity should be present between switch terminals No. 1 and 2. Replace switch as necessary. If switch is okay, go to next step.
2. Disconnect rear sunshade switch 22-pin connector. (Scheme 16) With switch off, no continuity should be present between any switch terminal. With switch on, continuity should be present between switch terminals No. 6 and 7. Replace switch as necessary. If switch is okay, go to next step.
3. Disconnect rear sunshade relay 5-pin connector. (Scheme 16) Check wire harness side of connector. Replace rear sunshade relay as necessary. If relay is okay, reconnect relay connector. Backprobe connector at wire harness side. See «REAR SUNSHADE RELAY TEST»(ref-27018-S37259871392001031200000) table. REAR SUNSHADE RELAY TEST Terminals No. Condition Specification Relay Connector Disconnected 3 & Ground Rear Sunshade Switch Off No Continuity 3 & Ground Rear Sunshade Switch On Continuity 5 & Ground At All Times Continuity 1 & Ground Ignition Switch In OFF Or ACC No Voltage 1 & Ground Ignition On Battery Voltage Relay Connector Connected (Backprobe) 2 & Ground Ignition On & Shift Lever In "P" No Voltage 2 & Ground Ignition On & Shift Lever In "R" Battery Voltage 4 & Ground Ignition On & Rear Sunshade Switch (Rear Seat Control Switch) On No Voltage 4 & Ground Ignition On & Rear Sunshade Switch (Rear Seat Control Switch) Off Battery Voltage

SEAT BELT TENSION REDUCER SOLENOID

Disconnect seat belt tension reducer solenoid 2-pin connector. Connect battery positive lead to connector terminal No. 1 and battery negative lead to connector terminal No. 2. (Scheme 17) Pull belt upward. belt should slowly retract when released. Disconnect battery leads. Pull belt upward. Belt should retract quickly. If solenoid does not operate as specified, replace outer belt assembly.

Scheme 17

SHOULDER BELT ANCHOR MOTOR & SENSOR

Disconnect shoulder belt anchor sensor 6-pin connector. (Scheme 18) Connect positive battery voltage to terminal No. 6 and negative battery voltage to terminal No. 4. Slider should move upward. Reverse polarity. Slider should move downward. If slider does not operate as specified, replace anchor motor.

Scheme 18

STOPLIGHT SWITCH

Disconnect 4-pin stoplight switch connector (located on brake pedal support). Check continuity between stoplight switch terminals No. 1 and 2. With switch pin pushed in (brake pedal released), continuity should exist between terminals No. 1 and 2. (Scheme 19) If continuity is not as specified, replace stoplight switch and retest system operation.

Scheme 19

PIN VOLTAGE TESTS

Using a DVOM, backprobe to measure voltage at appropriate body ECU. (Scheme 20)- (Scheme 32).

Scheme 20

Scheme 21

Scheme 22

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Scheme 27

Scheme 28

Scheme 29

Scheme 30

Scheme 31

Scheme 32