Diagnosis System
- DESCRIPTION
The ECM 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 the CRUISE main indicator lamp does not illuminate after DTC check, there may be a problem with the cruise control system.
Use the hand-held tester to check and solve the problem.
- CHECK DLC3
- The 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
Symbols (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 If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
HINT:
Connect the cable of the hand-held tester to the DLC3, turn the ignition switch ON and attempt to use the tester. If the screen displays UNABLE TO CONNECT TO VEHICLE, a problem may be on the vehicle side or tester side.
- 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.
- The ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
- INSPECT BATTERY VOLTAGE
Standard: 11 to 14 V
If the voltage is below 11 V, recharge or replace the battery before proceeding.
- CHECK INDICATOR
- Turn the ignition switch ON.
- Check that the CRUISE main indicator lamp illuminates when the cruise control main switch is turned ON, and that the indicator lamp turns off when the main switch is turned OFF.
If the results are not as specified, inspect the CRUISE MAIN INDICATOR LAMP CIRCUIT .
- While driving with cruise control, the ECM activates AUTO CANCEL of the cruise control system when a malfunction in one of the following occurs: vehicle speed sensors, stop lamp switch or other related parts. When AUTO CANCEL is activated, the CRUISE main indicator lamp outputs the blinking pattern shown to the left. At the same time, data of the malfunction is stored in the ECM as Diagnostic Trouble Code (DTC).