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 CRUISE MAIN indicator light does not come on after the DTC check, there is a malfunction on the cruise control system.
- CHECK DLC3
- The ECM uses the ISO 15765-4 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.
ECU CONNECTOR TERMINALS AND SYMBOL DESCRIPTIONSymbols (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) CAN bus line Ignition switch OFF(1) 54 to 69 Ω CANH (6) - CG (4) HIGH-level CAN bus line Ignition switch OFF(1) 200 Ω or higher CANL (14) - CG (4) HIGH-level CAN bus line Ignition switch OFF(1) 200 Ω or higher CANH (6) - BAT (16) LOW-level CAN bus line Ignition switch OFF(1) 6 kΩ or higher CANL (14) - BAT (16) LOW-level CAN bus line Ignition switch OFF(1) 6 kΩ or higher NOTE:(1) Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. HINT:
Connect the cable of the intelligent tester to the DLC3, turn the power switch ON (IG) and attempt to use the tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the tester.
- If communication is normal when the tester is connected to another vehicle, inspect the DLC3 of the original vehicle.
- If communication is still not possible when the tester is connected to another vehicle, the problem may be in the tester itself. Consult the Service Department listed in the tester's instruction manual.
- CHECK INDICATOR
- Turn the ignition switch to ON.
- Check that the CRUISE main indicator light illuminates when the cruise control main switch is turned on, and that the indicator light turns off when the main switch is turned off. If the results are not as specified, inspect the CRUISE MAIN INDICATOR LIGHT CIRCUIT (See CRUISE MAIN INDICATOR LIGHT CIRCUIT
).
HINT:
While driving with cruise control, the ECM activates AUTO CANCEL of the cruise control system when a malfunction occurs in one of the following: vehicle speed sensors, stop light switch, or other related parts. When AUTO CANCEL is activated, the CRUISE main indicator light outputs the blinking pattern shown to the left. At the same time, data of the malfunction is stored as a DTC.