Pre-Collision System (Diagnostics - Introduction): Diagnosis Lexus LX J200

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

1. Use these procedures to troubleshoot the pre-collision system.
2. *: Use the Techstream.

1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
2. INSPECT BATTERY VOLTAGE Standard voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding. NEXT: Go to next step
3. CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM* Use the Techstream to check if the CAN communication system is functioning normally. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-385222-S11207754182011021400000) . RESULT Result Proceed to CAN DTC is not output A CAN DTC is output B B --> GO TO CAN COMMUNICATION SYSTEM. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING»(ref-385222-S11207754182011021400000) A: Go to next step
4. CHECK INDICATOR Check the indicator. Refer to «DIAGNOSIS SYSTEM»(ref-385309-S31194061642011021400000) . NEXT: Go to next step
5. CHECK FOR DTC* Check for DTCs. Refer to «DTC CHECK / CLEAR»(ref-385309-S01441144712011021400000) . Clear the DTCs. Refer to «DTC CHECK / CLEAR»(ref-385309-S01441144712011021400000) . Recheck for DTCs. Refer to «DTC CHECK / CLEAR»(ref-385309-S01441144712011021400000) . RESULT Result Proceed to DTC is not output A DTC is output B B --> GO TO DTC CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART»(ref-385309-S25672721872011021400000) A: Go to next step
6. PROBLEM SYMPTOMS TABLE Refer to the Problem Symptoms Table. Refer to «PROBLEM SYMPTOMS TABLE»(ref-385309-S11481546212011021400000) . RESULT Result Proceed to Fault is not listed in problem symptoms table A Fault is listed in problem symptoms table B B --> Go to step 8 A: Go to next step
7. OVERALL ANALYSIS AND TROUBLESHOOTING* Terminals of ECU. Refer to «TERMINALS OF ECU»(ref-385309-S01758751312011021400000) . Data List / Active Test. Refer to «DATA LIST / ACTIVE TEST»(ref-385309-S17033523372011021400000) . NEXT: Go to next step
8. ADJUST, REPAIR OR REPLACE NEXT: Go to next step
9. CONFIRMATION TEST NEXT --> END

PROBLEM SYMPTOMS TABLE

HINT

1. Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
2. Inspect the fuses and relays related to this system before inspecting the suspected areas below.

PRE-COLLISION SYSTEM

Scheme 77

1. CHECK SEAT BELT CONTROL ECU Disconnect the E41 and E42 seat belt control ECU connectors. Measure the voltage and resistance according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition E42-8 (IG1) - Body ground G - Body ground Seat belt control ECU power source line Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V E41-7 (+B) - Body ground R - Body ground Seat belt control ECU power source line Always 11 to 14 V E41-8 (PGND) - Body ground W-B - Body ground Seat belt control ECU ground line Always Below 1 ohms If the result is not as specified, there may be a malfunction on the wire harness side. Reconnect the E41 and E42 seat belt control ECU connectors. Measure the voltage according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition E41-2 (MOR+) - E41-8 (PGND) L - W-B Passenger side seat belt motor power source line Engine switch on (IG) 4 to 8.5 V E41-3 (MOL+) - E41-8 (PGND) GR - W-B Driver side seat belt motor power source line Engine switch on (IG) 4 to 8.5 V E41-1 (MOR-) - Body ground B - Body ground Passenger side seat belt motor ground line Engine switch on (IG) 4 to 8.5 V E41-4 (MOL-) - Body ground W - Body ground Driver side seat belt motor ground line Engine switch on (IG) 4 to 8.5 V If the result is not as specified, the seat belt control ECU may have a malfunction.

Scheme 78

Scheme 79

1. FUNCTION OF WARNING INDICATOR AND MESSAGE If the pre-collision system is not functioning properly, the driver is warned through the combination meter master warning indicator and the multi-information display warning message.
2. INITIAL CHECK The initial check occurs when the engine switch is off for more than 2 seconds, and then turned on (IG). The initial check consists of the pre-collision system diagnostic check which lasts approximately 3 seconds. If a malfunction is detected during the initial check, the multi-information display displays "Check PCS System" or "PCS Not available now". Warning Message Detail DTC PCS Warning Indicator Check PCS System This message appears when the seat belt control ECU detects a system malfunction DTC is output ON PCS Not available now This message appears when the seat belt control ECU is in the fail-safe mode DTC is not output Blinking
3. CONSTANT CHECK After completing the initial check, the pre-collision system will become operational. Then, the diagnosis circuit will perform a constant check to check that there is not a system malfunction. If a malfunction is detected during the constant check, the multi-information display displays "Check PCS System" or "PCS Not available now".

DTC CHECK / CLEAR

1. CHECK DTC Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Pre-Collision / Trouble Codes. Read the DTCs.
2. CLEAR DTC Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / Pre-Collision / Trouble Codes. Clear the DTCs.

DATA LIST / ACTIVE TEST

1. READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time. NOTE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Body Electrical / (desired system) / Data List. According to the display on the Techstream, read the Data List. PRE-COLLISION Tester Display Measurement Item/Range Normal Condition Diagnostic Note Driver Buckle SW Driver side buckle switch status / UNSET, SET or NG UNSET: Driver side seat belt unfastened SET: Driver side seat belt fastened NG: Indeterminate data - Passenger Buckle SW Front passenger side buckle switch status / UNSET, SET or NG UNSET: Passenger side seat belt unfastened SET: Passenger side seat belt fastened NG: Indeterminate data - Driver Belt Control Seat belt control status of driver side seat / STOP, ON or ERROR STOP: Control stopped ON: Controlled ERROR: Indeterminate data The driver side seat belt is fastened. Passenger Belt Control Seat belt control status of passenger side seat / STOP, ON or ERROR STOP: Control stopped ON: Controlled ERROR: Indeterminate data The passenger side seat belt is fastened. Number of Trouble Codes Number of stored trouble codes / Min.: 0, Max.: 255 Number of DTCs stored - COMBINATION METER Tester Display Measurement Item/Range Normal Condition Diagnostic Note Vehicle Speed Meter Vehicle speed/ Min.: 0 km/h (0 mph) Max.: 255 km/h (158 mph) Almost same as actual speed (when driving) The speed is indicated on the speedometer.
2. PERFORM ACTIVE TEST HINT: Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: All ECUs / (desired system) / Active Test. According to the display on the Techstream, perform the Active Test. PRE-COLLISION Tester Display Test Part Control Range Diagnostic Note Driver Seat Belt Motor Driver side seat belt motor OFF or ON The driver side seat belt is fastened. Passenger Seat Belt Motor Passenger side seat belt motor OFF or ON The passenger side seat belt is fastened. Driver and Passenger Seat Belt Motor Driver and passenger side seat belt motors OFF or ON The driver and passenger side seat belts are fastened. ABS/VSC/TRAC Tester Display Test Part Control Range Diagnostic Note Buzzer Skid control buzzer sounds OFF or ON

DIAGNOSTIC TROUBLE CODE CHART

HINT

If a trouble code is output during the DTC check, inspect the trouble areas listed for that code. For details of the code, refer to the "See" below.

PRE-COLLISION SYSTEM