Diagnosis System
- DESCRIPTION
The ECU controls the cruise control system of the vehicle. The data and DTCs relating to the cruise control system can be read from the DLC3 of the vehicle. If either DTC or CRUISE OK is not displayed in the multi-information display on the combination meter when checking for DTCs, there may be a problem with the combination meter or the CAN communication and multiplex communication system.
Use the hand-held tester to check and solve the problem.
- CHECK THE DLC3
- The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.DLC3 CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Symbols (Terminals 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 Ω SG(5) - Body ground Signal ground Always Below 1 Ω BAT(16) - Body ground Battery positive Always 11 to 14 V CANH(6) - CANL(14) HIGH-level CAN bus line IG switch OFF 54 to 67 Ω CANH(6) - Battery positive HIGH-level CAN bus line IG switch OFF 1 MΩ or higher CANH(6) - CG(4) HIGH-level CAN bus line IG switch OFF 3 kΩ or higher CANL(14) - Battery positive LOW-level CAN bus line IG switch OFF 1 MΩ or higher CANL(14) - CG(4) LOW-level CAN bus line IG switch OFF 3 kΩ or higher HINT:
If the display shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the hand-held tester to the DLC3, turned the ignition switch to the ON position and operated the tester, there is a problem on either the vehicle side or the tool side.
- If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
- If communication is still impossible 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.
- The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
- CHECK THE INDICATOR
- Turn the ignition switch to the ON position.
- Check that the CRUISE main indicator light comes on when the cruise control main switch ON-OFF button is push on, and that the indicator light goes off when the ON-OFF button is pushed off.
HINT:
If there is a problem with the indicator, inspect the CRUISE MAIN INDICATOR LIGHT CIRCUIT .
HINT:
If a malfunction occurs in the vehicle speed sensors, stop lamp switch assy, or other related parts during cruise control driving, the ECM actuates AUTO CANCEL of the cruise control and then the CRUISE main indicator light starts to blink, informing the driver of the malfunction. At the same time, data of the malfunction is stored as a diagnostic trouble code (DTC).