Trouble Shooting

NOTE: Prior to trouble shooting, ensure no problems exist in multiplex communications. If problems exist, repair multiplex control system before trouble shooting. See MULTIPLEX CONTROL SYSTEMS - LS430 article.

NOTE: Check circuits and components in listed order. See BODY NO. 2 CONTROL SYSTEM , BODY NO. 3 CONTROL SYSTEM , BODY NO. 4 CONTROL SYSTEM and BODY NO. 5 CONTROL SYSTEM table. If circuits or components are okay, return to trouble shooting and identify next circuit to be checked.

BODY NO. 2 CONTROL SYSTEM

Problem

Inspect

Lighting System

Headlights Do Not Operate (Low Beam)

⁽¹⁾ Light Control Switch Circuit
⁽¹⁾ Headlight Relay Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU

Headlights Do Not Operate (High Beam Or Flash)

⁽¹⁾ High-Beam Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Front Light ECU
⁽³⁾ Body No. 2 ECU

Automatic Light Control System Does Not Operate

⁽⁴⁾ Automatic Light Control Sensor Circuit
⁽²⁾ Combination Switch
⁽³⁾ Front Light ECU
⁽³⁾ Body No. 2 ECU

Both Headlights Do Not Operate

⁽¹⁾ Headlight Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Front Light ECU
⁽³⁾ Body No. 2 ECU

Fog Lights Do Not Operate

⁽¹⁾ Fog Light Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Front Light ECU
⁽³⁾ Body No. 2 ECU

Rear Combination Light Does Not Operate

⁽¹⁾ Power Source Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

Both Taillights Do Not Operate

⁽¹⁾ Taillight Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

Stoplights Do Not Operate

⁽¹⁾ Stoplight Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

High-Mounted Stoplight Does Not Operate

⁽¹⁾ High-Mounted Stoplight Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

Back-Up Lights Do Not Operate

⁽¹⁾ Back-Up Light Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

License Plate Light Does Not Operate

⁽¹⁾ License Plate Light Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU
⁽³⁾ Body No. 4 ECU

Parking Lights Does Not Operate

⁽¹⁾ Parking Light Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 5 ECU
⁽³⁾ Body No. 2 ECU

Side Marker Lights Do Not Operate

⁽¹⁾ Side Marker Light Circuit
⁽²⁾ Combination Switch Circuit
⁽³⁾ Body No. 5 ECU
⁽³⁾ Body No. 2 ECU

Automatic Light Turn-Off System Does Not Operate (Headlights Normal)

⁽¹⁾ Headlight Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 2 ECU

Turn Signal & Hazard Warning System

Hazard Warning Light Does Not Operate

⁽¹⁾ Hazard Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 5 ECU
⁽³⁾ Body No. 2 ECU

All Turn Signal Lights Do Not Operate

⁽¹⁾ Turn Signal Light Circuit
⁽¹⁾ Light Control Switch Circuit
⁽²⁾ Combination Switch
⁽³⁾ Body No. 5 ECU
⁽³⁾ Body No. 2 ECU

Illumination Light System

All Switch Illumination Does Not Operate

⁽¹⁾ Power Source Circuit
⁽¹⁾ Rheostat Light Control Volume Circuit
⁽³⁾ Body No. 2 ECU

Some Switch Illumination Does Not Operate

⁽¹⁾ Illumination Light Circuit
⁽³⁾ Body No. 2 ECU

Brightness Does Not Change (All)

⁽¹⁾ Rheostat Light Control Volume Circuit
⁽³⁾ Body No. 2 ECU

Brightness Does Not Change (Cluster Only)

⁽¹⁾ Rheostat Light Control Volume Circuit
⁽¹⁾ Instrument Cluster Circuit
⁽³⁾ Body No. 2 ECU

Driver Seat Belt Buckle Does Not Illuminate

⁽¹⁾ Driver Buckle Illumination Circuit
⁽³⁾ Body No. 2 ECU

Glove Compartment Door Light Does Not Illuminate

⁽¹⁾ Illumination Light Circuit
⁽³⁾ Body No. 2 ECU

Stoplight System

Stoplights Do Not Operate

⁽¹⁾ Stoplight Switch Circuit
⁽¹⁾ Stoplight Circuit
⁽³⁾ Body No. 2 ECU

Headlight Cleaner System

Headlight Cleaner System Does Not Operate

Headlight Cleaner Nozzle & Hose
⁽¹⁾ Headlight Cleaner Switch Circuit
⁽¹⁾ Headlight Cleaner Motor Circuit
⁽¹⁾ Headlight Cleaner Relay Circuit
⁽³⁾ Body No. 2 ECU

Driver Seat Belt System

Driver Seat Belt Warning Does Not Illuminate

⁽¹⁾ Driver Buckle Switch Circuit
⁽³⁾ Body No. 2 ECU

Driver Seat Belt Electric Tension Reducer System Does Not Operate

⁽¹⁾ Driver Buckle Switch Circuit
⁽¹⁾ Driver Tension Reducer Circuit
⁽³⁾ Body No. 2 ECU

Power Shoulder Belt Anchorage System

Driver Belt Anchor Cannot Be Operated Manually

⁽¹⁾ Power Source Circuit
⁽¹⁾ Shoulder Belt Anchor Motor Circuit
⁽¹⁾ Shoulder Belt Anchor Sensor Circuit
⁽³⁾ Driver Door ECU
⁽³⁾ Body No. 2 ECU

Additional Systems

Stoplight Switch Signal Is Sent To Shift Lock, VSC and Engine Control System

⁽¹⁾ Stoplight Switch Circuit
⁽³⁾ Body No. 2 ECU

⁽¹⁾	Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.

⁽²⁾	See STEERING COLUMN SWITCHES article.

⁽³⁾	Perform appropriate pin voltage test under PIN VOLTAGE TESTS .

⁽⁴⁾	See appropriate Diagnostic Trouble Code (DTC) test under SELF-DIAGNOSTIC SYSTEM.

BODY NO. 3 CONTROL SYSTEM

Problem

Inspect

Interior Light System

All Interior Lights Do Not Operate

⁽¹⁾ Power Source Circuit
⁽¹⁾ Illumination Light Circuit
⁽²⁾ Body No. 3 ECU

Seat Belt Buckle Illumination Does Not Operate

⁽¹⁾ Passenger Buckle Illumination Circuit
⁽²⁾ Body No. 3 ECU

Outer Step Light (In Outer Mirror) Does Not Operate

⁽¹⁾ Illumination Circuit
⁽²⁾ Body No. 3 ECU

Passenger Seat Belt System

Passenger Seat Belt Electric Tension Reducer System Does Not Operate

⁽¹⁾ Passenger Buckle Switch Circuit
⁽¹⁾ Passenger Tension Reducer Circuit
⁽²⁾ Body No. 3 ECU

Power Shoulder Belt Anchorage System

Passenger Belt Anchor Cannot Be Operated Manually

⁽¹⁾ Shoulder Belt Anchor Motor Circuit
⁽²⁾ Body No. 3 ECU
⁽³⁾ Driver Door ECU

Wiper & Washer System

Wiper & Washer System Does Not Operate

⁽¹⁾ Power Source Circuit
⁽¹⁾ Wiper Motor Circuit
⁽²⁾ Body No. 3 ECU

Wiper System Does Not Operate (High Speed)

⁽¹⁾ Wiper High Switch Circuit
⁽²⁾ Body No. 3 ECU

Washer Fluid Does Not Operate

Washer Hose & Nozzle

With Wiper At High Position, Wiper Blade Is In Contact With Body. With Wiper Switch Off, Wiper Blade Does Not Retract Or Retract Position Is Wrong.

⁽¹⁾ Wiper High Switch Circuit
⁽¹⁾ Wiper Motor Circuit
⁽²⁾ Body No. 3 ECU

Washer System Does Not Operate

⁽¹⁾ Washer Motor Does Not Operate
⁽²⁾ Body No. 3 ECU

Washer Fluid Level Warning System Does Not Operate

⁽¹⁾ Washer Fluid Level Warning Switch Circuit
⁽²⁾ Body No. 3 ECU

Additional Systems

Navigation System Abnormal

⁽¹⁾ Navigation ECU Communication Circuit,
⁽¹⁾ Navigation ECU
⁽¹⁾ Multi Display ECU
⁽²⁾ Body No. 3 ECU

Shift Point Too High Or Too Low

⁽¹⁾ Pattern Select Switch Circuit
⁽¹⁾ Shift Lock ECU

Rear Sunshade Abnormal

⁽¹⁾ Rear Sunshade ECU Circuit
⁽²⁾ Body No. 3 ECU

Brake Pad Indicator Does Not Operate

⁽¹⁾ Instrument Cluster
⁽¹⁾ Brake Pad Sensor
⁽⁴⁾ABS System

Rear Seat Control System Does Not Operate

⁽¹⁾ Rear Seat Return Switch Circuit
⁽³⁾ Right Or Left Rear Seat ECU
⁽²⁾ Body No. 3 ECU

⁽¹⁾	Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.

⁽²⁾	Perform appropriate pin voltage test under PIN VOLTAGE TESTS .

⁽³⁾	See MULTIPLEX CONTROL SYSTEMS - LS430 article.

⁽⁴⁾	See ANTI LOCK - LS430 article in BRAKES.

BODY NO. 4 CONTROL SYSTEM

Problem

Inspect

Luggage Room Junction Block Control System Does Not Operate

⁽¹⁾ Power Source Circuit
⁽¹⁾ Ignition Switch Power Source Circuit
⁽²⁾ Body No. 4 ECU

Rear A/C Does Not Operate

⁽¹⁾ Rear A/C Amplifier Circuit
⁽³⁾ A/C ECU
⁽²⁾ Body No. 4 ECU

Fuel Lid Opener System Does Not Operate

⁽¹⁾ Fuel Lid Opener Motor Circuit
⁽²⁾ Body No. 4 ECU

Luggage Compartment Door Opener Or Closer System Does Not Operate

⁽¹⁾ Luggage Compartment Door Opener Switch Circuit
⁽¹⁾ Luggage Compartment Door Courtesy Switch Circuit
⁽¹⁾ Luggage Compartment Door Switch Circuit
⁽¹⁾ Luggage Compartment Door Key Lock & Unlock Switch Circuit
⁽¹⁾ Luggage Door Lock Switch Circuit
⁽¹⁾ Luggage Compartment Door Motor Circuit
⁽²⁾ Body No. 4 ECU

Fuel Sender Gauge Does Not Operate

⁽⁴⁾ Fuel Sender Gauge Circuit
⁽²⁾ Body No. 4 ECU

Luggage Compartment Light Does Not Light

⁽¹⁾ Luggage Compartment Light Circuit
⁽¹⁾ Luggage Compartment Door Courtesy Switch Circuit
⁽²⁾ Body No. 4 ECU

⁽¹⁾ Rear Seat Belt Buckle Light Does Not Come On

⁽¹⁾ Rear Seat Belt Buckle Illumination Light Circuit
⁽²⁾ Body No. 4 ECU

⁽¹⁾	Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.

⁽²⁾	Perform appropriate pin voltage test under PIN VOLTAGE TESTS .

⁽³⁾	See AUTOMATIC A/C-HEATER SYSTEMS - LS430 article in AIR CONDITIONING & HEATING.

⁽⁴⁾	See INSTRUMENT PANELS - LS430 article.

BODY NO. 5 CONTROL SYSTEM

Problem

Inspect

Front Light Control Systems (Headlights, Clearance Lights, Front Fog Lights, Horn, Washer System and Washer Fluid Level Warning

⁽¹⁾ Power Source Circuit
⁽¹⁾ Ignition Switch Power Source Circuit
⁽²⁾ Body No. 5 ECU

Horn Does Not Sound

⁽¹⁾ Horn Circuit
⁽²⁾ Body No. 5 ECU

⁽¹⁾	Perform appropriate circuit test under CIRCUIT TESTS . If more than one circuit test is listed, perform tests in order listed.

⁽²⁾	Perform appropriate pin voltage test under PIN VOLTAGE TESTS .