Cruise Control System Diagnosis System
DESCRIPTION
CHECK DLC3
CHECK INDICATOR
Cruise Control System -- Diagnosis System |
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 light does not illuminate after the DTC check, there may be a problem with the cruise control system. Use the intelligent tester to check and solve the problem.

|
The ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with ISO 15031-03 and matches the ISO 9141-2 format.
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 Ω
|
SG (5) - Body ground
| Signal ground
| Always
| Below 1 Ω
|
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 intelligent tester to the DLC3, turn the ignition switch ON 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.
Turn the ignition switch 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 (Toyota Fortuner RM000000PLV00FX.html).
- HINT:
- 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 light switch or other related parts. When AUTO CANCEL is activated, the CRUISE main indicator light outputs the blinking pattern shown in the illustration. At the same time, data of the malfunction is stored as a DTC.