Trouble Shooting

Verify customer complaint. Perform a visual inspection, checking for open fuses, disconnected or damaged wire harnesses and components. Ensure all fluid levels are correct. Repair or replace items as necessary and recheck.

Verify proper multiplex control system operation and ensure no Diagnostic Trouble Codes (DTC) are present. See MULTIPLEX CONTROL SYSTEMS - LS400 article. Repair as necessary. If no DTCs are present, diagnose by symptom. See appropriate SYMPTOM DIAGNOSIS table.

SYMPTOM DIAGNOSIS (GAUGES)

Symptom

Inspect

Speedometer Inoperative Or Abnormal Operation

⁽¹⁾ Speedometer Circuit
⁽¹⁾ Speed Sensor Circuit

Tachometer Inoperative Or Abnormal Operation

⁽¹⁾ Tachometer Circuit
⁽¹⁾ Igniter Signal Circuit

Fuel Gauge Inoperative Or Abnormal Operation

⁽¹⁾ Fuel Gauge Circuit
⁽²⁾ Wire Harness
⁽³⁾ Instrument Cluster

Engine Coolant Temperature Gauge Inoperative Or Abnormal Operation

⁽¹⁾ Engine Coolant Temperature Gauge Circuit
⁽²⁾ Wire Harness
⁽³⁾ Instrument Cluster

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

⁽²⁾	Inspect wire harness and repair as necessary. See WIRING DIAGRAMS .

⁽³⁾	See INSTRUMENT CLUSTER CIRCUIT under CIRCUIT TESTS.

SYMPTOM DIAGNOSIS (INDICATORS & WARNING LIGHTS)

Symptom

Inspect

Shift Indicator Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽²⁾ A/T Shift Indicator Light Switch
⁽²⁾ Transmission Control Switch

Open Door Warning Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽³⁾ Door Open Detection Switch

Driver's Seat Belt Warning Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽⁴⁾ Driver's Seat Belt Buckle Switch Circuit

Passenger's Seat Belt Warning Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽⁴⁾ Passenger's Seat Belt Buckle Switch Circuit

Low Oil Pressure Warning Light Does Not Illuminate

⁽³⁾ Multi-Information Display
⁽³⁾ Engine Oil Pressure Switch

Discharge Warning Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽⁵⁾ Generator

Brake Warning Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽³⁾ Parking Brake Switch
⁽³⁾ Brake Fluid Level Warning Switch
⁽³⁾ Instrument Cluster

Headlight Indicator Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽⁶⁾ Headlight & Taillight System
⁽³⁾ Instrument Cluster

CRUISE MAIN Indicator Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽⁷⁾ Cruise Control Switch
⁽³⁾ Instrument Cluster

ECT SNOW Indicator Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽²⁾ ECT Pattern Indicator Signal
⁽³⁾ Instrument Cluster

ECT PWR Indicator Light Does Not Illuminate

⁽¹⁾ Bulb Circuit
⁽²⁾ ECT Pattern Indicator Signal
⁽³⁾ Instrument Cluster

VSC OFF Indicator Light Does Not Illuminate

⁽³⁾ Multi-Information Display
⁽⁸⁾ ABS, TRAC & VSC ECU
⁽³⁾ Instrument Cluster

Washer Level Warning Light Does Not Illuminate

⁽³⁾ Multi-Information Display
⁽³⁾ Washer Fluid Level Warning Switch
⁽³⁾ Instrument Cluster

Rear Lights Warning Light Does Not Illuminate

⁽³⁾ Multi-Information Display
⁽³⁾ Light Failure Sensor
⁽³⁾ Instrument Cluster

Engine Oil Level Warning Light Does Not Illuminate

⁽³⁾ Multi-Information Display
⁽³⁾ Engine Oil Level Warning Switch
⁽³⁾ Instrument Cluster

All Indicator & Warning Lights Do Not Illuminate

⁽¹⁾ Bulb Circuit
⁽¹⁾ Combination Meter ECU Power Source Circuit
⁽³⁾ Instrument Cluster

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

⁽²⁾	See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.

⁽³⁾	See appropriate test under COMPONENT TESTS .

⁽⁴⁾	See appropriate BODY CONTROL SYSTEMS article.

⁽⁵⁾	See GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.

⁽⁶⁾	See appropriate wiring diagram in EXTERIOR LIGHTS article.

⁽⁷⁾	See appropriate CRUISE CONTROL SYSTEMS article.

⁽⁸⁾	See appropriate ANTI-LOCK/TRACTION CONTROL SYSTEMS article in BRAKES.