Section 344 (Driver Door Control System - Diagnosis): Pre-Check

WARNING: This page is about a different car, the 2004 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSIS SYSTEM
1. Description
  ECU data of this system can be read from DLC3 of the vehicle.
  
  Therefore, when there seems to be a trouble on this system, use hand-held tester to check and troubleshoot it.
  
  Fig 1: Connecting Hand-Held Tester To DLC3
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the DLC3.
  The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
  
  Fig 2: Identifying DLC3
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 3: Terminal Condition Chart
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  If the display shows "UNABLE TO CONNECT TO VEHICLE" when the cable of the hand- held tester is connected to DLC3, the ignition switch is turned ON and the hand held tester is connected, there is a problem either on the vehicle side or tool side.
  - If communication is normal when the tool is connected to another vehicle, inspect DLC3 on the original vehicle.
  - If communication does not function when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department listed in the tool's instruction manual.
USING HAND-HELD TESTER
1. Hook up the hand-held tester to DLC3.
2. Monitor the ECU data by following the prompts on the tester screen.
  HINT:
  
  Hand-held tester has a "Snapshot" function which records the monitored data. Refer to the hand-held tester operator manual for further details.
DATA LIST
HINT:

By the DATA LIST displayed on the hand-held tester, you can read the value of the switch, sensor, actuator and so on without removing any parts. Reading the DATA LIST as a first step of troubleshooting is one of the method to shorten the labor time.
1. Connect the hand-held tester to DLC3.
2. Turn the ignition switch ON.
3. According to the display on tester, read "DATA LIST".
Power window master switch:

Fig 4: Diagnostic Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Body ECU (Main):

Fig 5: Diagnostic Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
ACTIVE TEST
HINT:

Performing ACTIVE TEST using the hand-held tester allows the relay, VSV, actuator and so on to operate without removing any parts. Performing ACTIVE TEST as a first step of troubleshooting is one of the method to shorten the labor time.

DATA LIST can be displayed during the ACTIVE TEST.
1. Connect the hand-held tester to DLC3.
2. Turn the ignition switch ON.
3. According to the display on tester, perform the "ACTIVE TEST".
Power window master switch:

Fig 6: Diagnostic Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Body ECU (Main):

Fig 7: Diagnostic Chart
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002