Diagnosis System

DIAGNOSIS FUNCTION
1. The diagnosis function makes the master warning light and the multi-information display come on, and the CRUISE main indicator light blinks as shown in the illustration. When a malfunction occurs in the dynamic laser cruise control system, the DTCs are stored in the ECM.
NOTE:
- The master warning light goes off if the system returns to normal condition.
  
  Fig 1: Identifying Illumination Of Cruise Main Indictor Light And Master Warning Light
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Since the stored data in the ECM is erased by disconnecting the EFI and ETCS fuses or the battery terminal, do not disconnect them until the inspection has been completed.
DESCRIPTION
1. The ECM controls the cruise control function and dynamic laser cruise control in a vehicle. Data on the cruise control system, dynamic laser cruise control system and the DTCs can be read from DLC3 in the vehicle. If the CRUISE main indicator light does not come on after the DTC check, there is a malfunction in the cruise control and dynamic laser cruise control system.
  Use the intelligent tester to check and solve the problem.
  
  Fig 2: Cruise Main Indicator Light Blinking Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK 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 3: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 TERMINALS DESCRIPTION AND SPECIFIED CONDITION TABLE

Terminal No.	Connection / Specified Condition	Condition
4	Chassis ground - Body ground / 1 Ω or less	Always
7	Bus "+" line / Pulse generation	During Communication
16	Battery positive - Body ground / 9 to 14 V	Always

HINT:

If the display shows "UNABLE TO CONNECT TO VEHICLE" after connecting the intelligent tester to the DLC3 and turning the ignition ON, there is a problem either with the vehicle or with the tool.

If communication is normal when connecting the tool to another vehicle, inspect the DLC3 on the original vehicle.
If communication is still not possible when connecting the tool to another vehicle, the problem is probably in the tool itself. Consult the Service Department listed in the tool's instruction manual.

CHECK INDICATOR
1. Turn the ignition switch on.
2. Check that the CRUISE main indicator light and READY indicator come on when the main switch ON-OFF button is pushed on, and that the indicator light goes off when the ON-OFF button is pushed off.
  HINT:
  - If the indicator check result shows a problem, proceed to COMBINATION METER .
    
    Fig 4: Identifying Illumination Of Indicator And Warning Lights
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. If a malfunction occurs in the vehicle speed sensors, the stop light switch, or other related parts during cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and blinks the CRUISE main indicator light. This indicator light informs the driver of the malfunction. At the same time, the malfunction is stored as a diagnostic trouble code.
Fig 5: Cruise Main Indicator Light Blinking Pattern
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002