Diagnosis System
- DIAGNOSIS SYSTEM
- Inspect the battery voltage.
Standard voltage:
11 to 14 V
If the voltage is below 11 V, recharge the battery before proceeding.
- Check the DLC3. The 4WD control ECU uses CAN and the ISO 9141- 2 for communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format. Verify the conditions listed in TERMINALS SPECIFIED CONDITIONS TABLE .
TERMINALS SPECIFIED CONDITIONS TABLESymbols (Terminal No.) Terminal Description Condition Specified condition SIL (7) - SG (5) Bus "+" line During transmission Pulse generation CG (4) - Body ground Chassis ground Always Below 1 ohms SG (5) - Body ground Signal ground Always Below 1 ohms BAT (16) - Body ground Battery positive Always 11 to 14 V CANH (6) - CANL (14) HIGH-level CAN bus line Engine switch off 54 to 67 ohms CANH (6) - Battery positive HIGH-level CAN bus line Engine switch off 1 M ohms or higher CANH (6) - CG (4) HIGH-level CAN bus line Engine switch off 3 k ohms or higher CANL (14) - Battery positive LOW-level CAN bus line Engine switch off 1 M ohms or higher CANL (14) - CG (4) LOW-level CAN bus line Engine switch off 3 k ohms or higher HINT:
If the display shows a communication error message when the cable of the intelligent tester is connected to the DLC3, the engine switch is turned on (IG) and the intelligent tester is operated, there is a problem on either the vehicle side or the tester side.
- If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
- If communication is still not possible when the tester is connected to another vehicle, the problem is probably in the tester itself. Consult the Service Department listed in the tester's operator's manual.
- Inspect the battery voltage.
- FUNCTION OF 4WD INDICATOR
- The 4WD indicator light in the combination meter assembly (multi-information display) warns the driver of abnormal or poor condition of the four wheel drive control system.
- CHECK 4WD INDICATOR LIGHT
- Using SST, connect terminals TC and CG of the DLC3 (to enter the DTC output mode).
SST 09843-18040
- Turn the engine switch on (IG).
- "DIAG" is displayed on the multi-information display, and the 4WD control ECU checks the system for malfunctions.
- If the 4WD control system is normal, "DIAG 4WD OK" will be displayed on the multi-information display.
- If the 4WD control system is not normal, "DIAG 4WD XX (DTC)" will be displayed on the multi-information display.
- Although the Test Mode is not set for the 4WD control system, the message shown in Fig 6
will be displayed on the multi-information display when the Test Mode is activated to check the VSC, etc.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
HINT:
- Test Mode DTCs will not be stored because the Test Mode is not set.
- On the multi-information display, VSC, TIRE PRESSURE and 4WD are displayed in order.
- If the systems above are not displayed on the multi-information display, there may be a malfunction in TC and CG Terminal Circuit .
- If the 4WD indicator light check result is not normal, proceed to troubleshooting for the 4WD indicator light circuit.
TROUBLESHOOTING REFERENCETrouble Area See procedure 4WD indicator light (Remains on) PROBLEM SYMPTOMS TABLE 4WD indicator light (Does not come on) - Using SST, connect terminals TC and CG of the DLC3 (to enter the DTC output mode).
- FAIL-SAFE FUNCTION
- If following malfunctions occur, the 4WD control ECU will stop the function of 4WD control system or partly change the function to control the system.
MALFUNCTION REFERENCE
| Malfunction | Control |
|---|---|
| Malfunction in a speed sensor | Stop the function |
| Malfunction in the steering angle sensor and throttle signal line | Partly change the function |