Trouble Shooting

Trouble shooting of a body control system complaint begins with verification of the customer problem.
- If problem occurs in driver side junction block (body No. 2) or luggage room junction block (body No. 4) control systems, go to step 3.
- If problem occurs in passenger side junction block (body No. 3) or front light (body No. 5) control systems, go to step 4.
If problem does not occur, go to next step.
If problem does not occur, review conditions under which problem occurred for customer and try to duplicate those conditions. For example, if the problem occurs on rainy days or during high humidity conditions, sprinkle water onto vehicle and see if malfunction occurs. DO NOT sprinkle water directly into engine compartment or onto electronic components. Visually inspect for signs of mechanical and electrical damage. Inspect for blown fuses and damaged relays. Inspect for loose or corroded connections, damaged wiring harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any aftermarket electronic equipment is properly installed. If fault is found, repair as necessary.
Check DTCs. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. If there is a normal code, go to the next step. If there is a malfunction code, go to step 5.

Determine problem symptom.

For driver side junction block (body No. 2) control system, see PROBLEM SYMPTOM INDEX (BODY NO. 2 CONTROL SYSTEM) table.
For passenger side junction block (body No. 3) control system, see PROBLEM SYMPTOM INDEX (BODY NO. 3 CONTROL SYSTEM) table.
For luggage room junction block (body No. 4) control system, see PROBLEM SYMPTOM INDEX (BODY NO. 4 CONTROL SYSTEM) table.
For front light (body No. 5) control system, see PROBLEM SYMPTOM INDEX (BODY NO. 5 CONTROL SYSTEM) table.

Go to step 6.

PROBLEM SYMPTOM INDEX (BODY NO. 2 CONTROL SYSTEM)

Symptom

Suspected Area ⁽¹⁾

Driver Seat Belt System

Driver Seat Belt Warning Does Not Light Up

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

Driver Seat Belt Electric Tension Reducer System Does Not Operate

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

Headlight Cleaner System

Headlight Cleaner System Does Not Operate

Headlight Cleaner Nozzle & Hose ⁽⁴⁾, Headlight Cleaner Switch Circuit ⁽²⁾, Headlight Cleaner Motor Circuit ⁽²⁾, Headlight Cleaner Relay Circuit ⁽²⁾, Body No. 2 ECU ⁽³⁾

Illumination Light System

All Switch Illumination Lights Do Not Light Up

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

Each Switch Illumination Light Does Not Light Up

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

Brightness Does Not Change Even When Rheostat Turned (All)

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

Brightness Does Not Change Even When Rheostat Turned (Meter Illumination)

Rheostat Light Control Volume Circuit ⁽²⁾, Combination Meter Circuit ⁽²⁾, Body No. 2 ECU ⁽³⁾

Driver Seat Belt Buckle Illumination Circuit

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

Glove Compartment Door Light Does Not Light Up

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

Lighting System

Headlight Does Not Light Up (Low Beam)

Light Control Switch Circuit ⁽⁵⁾, Headlight Relay Circuit ⁽²⁾, Combination Switch, Body No. 2 ECU ⁽³⁾

Headlight System Does Not Operate (HI Beam Or Flash)

Headlight (HI-Beam) Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 5 ECU ⁽³⁾, Body No. 2 ECU ⁽³⁾

Automatic Light Control System Does Not Operate

Automatic Light Control Sensor Circuit ⁽⁶⁾, Combination Switch, Body No. 5 ECU ⁽³⁾, Body No. 2 ECU ⁽³⁾

Both Left & Right Headlight Does Not Light Up

Headlight Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 5 ECU ⁽³⁾, Body No. 2 ECU ⁽³⁾

Front Fog Light Does Not Light Up

Front Fog Light Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 5 ECU ⁽³⁾, Body No. 2 ECU ⁽³⁾

Rear Combination Light Does Not Light Up (All)

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

Both Left & Right Taillights Do Not Light Up

Taillight Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 2 ECU ⁽³⁾, Body No. 4 ECU ⁽³⁾

Both Left & Right Stop Lights Do Not Light Up

Stop Light Circuit ⁽²⁾, Combination Switch, Body No. 2 ECU ⁽³⁾, Body No. 4 ECU ⁽³⁾

Hi-Mounted Stop Light Does Not Light Up

Hi-Mounted Stop Light Circuit ⁽²⁾, Combination Switch, Body No. 2 ECU ⁽³⁾, Body No. 4 ECU ⁽³⁾

Back-Up Light Does Not Light Up

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

License Plate Light Does Not Light Up

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

Parking Light Does Not Light Up

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

Slide Marker Light Does Not Light Up

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

Light Auto Turn Off System Does Not Operate (Headlight Is Normal)

Headlight Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 2 ECU ⁽³⁾

Taillight System Does Not Light Up

Taillight Circuit ⁽²⁾, Light Control Switch Circuit ⁽⁵⁾, Combination Switch, Body No. 4 ECU ⁽³⁾, Body No. 2 ECU ⁽³⁾

Power Shoulder Belt Anchorage System

Driver Belt Anchor Cannot Be Operated Manually

Body No. 2 ECU Power Source Circuit ⁽²⁾, Shoulder Belt Anchor Motor Circuit ⁽²⁾, Shoulder Anchor Sensor Circuit ⁽²⁾, Driver Door ECU ⁽⁷⁾, Body No. 2 ECU ⁽³⁾

Stop Light System

Stop Light System Does Not Light Up

Stop Light Switch Circuit ⁽²⁾, Stop Light Circuit ⁽²⁾, Body No. 2 ECU ⁽³⁾

Turn Signal & Hazard Warning System

Hazard Warning Light Does Not Light Up

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

Turn Signal Light Does Not Light Up (All)

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

Others

Stop Light Switch Signal Is Sent To Shift Lock, Vehicle Skid Control (VSC) & Engine Control Systems

Stop Light Switch Circuit ⁽²⁾, Body No. 2 ECU ⁽³⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Perform appropriate circuit test under CIRCUIT TESTS .

⁽³⁾	Check appropriate body ECU. See PIN VOLTAGE TESTS .

⁽⁴⁾	Refer to appropriate WIPER/WASHER & HEADLIGHT CLEANER SYSTEM article.

⁽⁵⁾	Perform appropriate circuit test in appropriate STEERING COLUMN SWITCHES article.

⁽⁶⁾	Refer to DTC B1244: LIGHT SENSOR CIRCUIT MALFUNCTION under DIAGNOSTIC TESTS.

⁽⁷⁾	Check the driver door ECU. See PIN VOLTAGES in appropriate AIRBAG article in RESTRAINTS.

PROBLEM SYMPTOM INDEX (BODY NO. 3 CONTROL SYSTEM)

Symptom

Suspected Area ⁽¹⁾

Electronically Controlled Transmission System

Shift Point Too High Or Too Low

Pattern Select Switch Circuit ⁽²⁾, Shift Lock ECU ⁽³⁾

Interior Light System

All Interior Lights Do Not Light Up

Body No. 3 ECU Power Source Circuit ⁽²⁾, Illumination Light Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Buckle Illumination Light Does Not Light Up

Passenger Buckle Illumination Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Outer Step Light Does Not Light Up (In Outer Mirror)

Illumination Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Navigation System

Navigation System Is Abnormal

Navigation ECU Communication Circuit ⁽²⁾, Navigation ECU ⁽⁵⁾, Multi Display ECU ⁽⁶⁾, Body No. 3 ECU ⁽⁴⁾

Passenger Seat Belt System

Passenger Seat Belt Electric Tension Reducer System Does Not Operate

Passenger Buckle Switch Circuit ⁽⁷⁾, Passenger Tension Reducer Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Power Shoulder Belt Anchorage System

Passenger Belt Anchor Cannot Be Operated Manually

Shoulder Belt Anchor Motor Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾, Driver Door ECU ⁽¹³⁾

Rear Seat Control System

Rear Seat Control System Does Not Operate

Rear Seat Return Switch Circuit ⁽²⁾, Rear RH Or LH Seat ECU ⁽⁸⁾, Body No. 3 ECU⁽⁴⁾

Rear Sunshade System

Rear Sunshade Is Abnormal

Rear Sunshade ECU Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Warning Light

Brake Pad Indicator Does Not Light Up

Combination Meter System ⁽⁹⁾, Brake Pad Sensor Circuit ⁽²⁾, Anti-Lock Brake System (ABS) ⁽¹⁰⁾, Skid Control ECU ⁽¹¹⁾

Wiper & Washer System

Wiper & Washer System Does Not Operate (All)

Body No. 3 ECU Power Source Circuit ⁽²⁾, Wiper Motor Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Wiper System Does Not Operates (HI Speed)

Wiper HI Switch Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Washer Fluid Does Not Operate

Washer Hose & Nozzle ⁽¹²⁾

When Wiper Switch Is At HI Position, The Wiper Blade Is In Contact With The Body & When The Wiper Switch Is OFF, The Wiper Blade Does Not Retract Or The Retract Position Wrong

Wiper HI Switch Circuit ⁽²⁾, Wiper Motor Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Washer System Does Not Operate

Washer Motor Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

Washer Fluid Level Warning System Does Not Operate

Washer Fluid Level Warning Switch Circuit ⁽²⁾, Body No. 3 ECU ⁽⁴⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Perform appropriate circuit test under CIRCUIT TESTS .

⁽³⁾	Check the shift lock ECU. See PIN VOLTAGE TESTS in SHIFT INTERLOCK SYSTEMS article under AUTOMATIC TRANSMISSION in TRANSAXLE/TRANSMISSION.

⁽⁴⁾	Check body No. 3 ECU. See PIN VOLTAGE TESTS .

⁽⁵⁾	Check the navigation ECU. Further diagnosis information is not available.

⁽⁶⁾	Check the multi display ECU. Further diagnosis information is not available.

⁽⁷⁾	Check the passenger buckle switch circuit. See DTC 26/B0121 & B0122: RIGHT SEAT BELT BUCKLE SWITCH MALFUNCTION under DIAGNOSTIC TESTS in AIR BAG RESTRAINT SYSTEMS article.

⁽⁸⁾	Check the rear RH or LH seat ECU. See PIN VOLTAGE TESTS in appropriate POWER & HEATED SEATS article.

⁽⁹⁾	Check the combination meter system. See appropriate INSTRUMENT PANEL article.

⁽¹⁰⁾	Check the anti-lock brake system. See appropriate ANTI-LOCK BRAKES article in BRAKES.

⁽¹¹⁾	Check the skid control ECU. See PIN VOLTAGE TESTS in appropriate ANTI-LOCK BRAKES article in BRAKES.

⁽¹²⁾	Refer to appropriate WIPER/WASHER & HEADLIGHT CLEANER SYSTEMS article.

⁽¹³⁾	Check the driver door ECU. See PIN VOLTAGES in appropriate PASSIVE RESTRAINTS article in RESTRAINTS.

PROBLEM SYMPTOM INDEX (BODY NO. 4 CONTROL SYSTEM)

Symptom

Suspected Area ⁽¹⁾

Luggage Room Junction Block (Body No. 4) ECU System Does Not Operate (All)

Body No. 4 ECU Power Source Circuit ⁽²⁾, Ignition Switch Power Source Circuit (Body No. 4 ECU) ⁽²⁾, Body No. 4 ECU ⁽³⁾

Rear A/C System Does Not Operate

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

Fuel Lid Opener System Does Not Operate

Fuel Lid Opener Motor Circuit ⁽²⁾, Body No. 4 ECU ⁽³⁾

Luggage Compartment Door Opener Or Closer System Does Not Operate

Luggage Compartment Door Opener Switch Circuit ⁽²⁾, Luggage Compartment Door Courtesy Switch Circuit ⁽²⁾, Luggage Compartment Door (LOPN, LCLS) Switch Circuit ⁽²⁾, Luggage Compartment Door Key Lock & Unlock Switch Circuit ⁽²⁾, Door Lock Switch (Luggage) Circuit , Luggage Compartment Door Motor Circuit ⁽²⁾, Body No. 4 ECU ⁽³⁾

Fuel Sender Gauge Does Not Operate

Fuel Sender Gauge Circuit ⁽²⁾, Body No. 4 ECU ⁽³⁾

Luggage Compartment Light Does Not Light Up

Luggage Compartment Light Circuit ⁽²⁾, Luggage Compartment Door Courtesy Switch Circuit ⁽²⁾, Body No. 4 ECU ⁽³⁾

Rear Seat Belt Buckle Illumination Light Does Not Light Up

Rear Seat Belt Buckle Illumination Light Circuit ⁽²⁾, Body No. 4 ECU ⁽³⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Perform appropriate circuit test under CIRCUIT TESTS .

⁽³⁾	Check body No. 4 ECU. See PIN VOLTAGE TESTS .

⁽⁴⁾	Check the A/C ECU. Further diagnosis information is not available.

PROBLEM SYMPTOM INDEX (BODY NO. 5 CONTROL SYSTEM)

Symptom

Suspected Area ⁽¹⁾

Front Light Control Systems (Headlights, Clearance Lights, Front Fog Lights, Horn, Washer System & Washer Fluid Level Warning) Does Not Operate (All)

Body No. 5 Power Source Circuit ⁽²⁾, Ignition Power Source Circuit (Body No. 5 ECU) ⁽²⁾, Body No. 5 ECU ⁽³⁾

Horn Does Not Sound

Horn Circuit ⁽²⁾, Body No. 5 ECU ⁽³⁾

⁽¹⁾	Perform test procedures in order listed under suspected area.

⁽²⁾	Perform appropriate circuit test under CIRCUIT TESTS .

⁽³⁾	Check the front light (Body No. 5) ECU. See PIN VOLTAGE TESTS .

Go to the DTC chart. See DIAGNOSTIC TROUBLE CODE INDEX table.
Inspect the circuits and parts. See CIRCUIT TESTS .
After problem has been identified and repaired, confirm repairs. See CONFIRMATION TEST under SELF-DIAGNOSTIC SYSTEM.