Cruise Control System - Diagnostics: Pre-Check
- DIAGNOSIS SYSTEM
- Description
The ECM controls the cruise control function on this vehicle. Data of the cruise control or DTC can be read from the DLC3 of the vehicle. When cruise control function has a trouble, check CRUISE MAIN indicator does not light up but DTC inspection is performed.
Therefore, when the cruise control function seems to have a trouble, use the hand-held tester or SST to check and troubleshoot it.
- Check the DLC3.
The vehicle's ECM uses the ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with the SAE J1962 and matches the ISO 9141-2 format.
HINT:
If the display shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the cable of the hand-held tester to the DLC3, turned the ignition switch ON and operated the hand-held tester, there is a problem on the vehicle side or tool side.
- If the communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
- If the 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.
- Check the indicator.
- Turn the ignition switch ON.
- Check that the CRUISE MAIN in indicator light comes on when the cruise control main switch is turned ON, and that the indicator light goes off when the main switch is turned OFF.
HINT:
If the indicator check result is not normal, proceed to troubleshooting (See PROBLEM SYMPTOMS TABLE ) for the combination meter section.
- Check the DTC.
HINT:
If a malfunction occurs in the speed sensor or actuator, etc. during cruise control driving, the ECM actuates AUTO CANCEL of the cruise control and turns ON and OFF the CRUISE MAIN indicator light to inform the driver of a malfunction. At the same time, the malfunction is stored in the memory as a DTC.
- Output a DTC using diagnosis check wire.
- Turn the ignition switch ON.
- Using SST, connect terminals Tc and CG of the DLC3.
SST 09843- 18020
- Read the DTC on the CRUISE MAIN indicator light.
HINT:
- If a DTC is not output, inspect the diagnosis circuit.
- As an example, the blinking patterns for codes; normal and 52 are shown in the illustration.
- Description
- MONITOR ECM DATA BY USING HAND-HELD TESTER
- Hook up the hand-held tester to the DLC3.
- Monitor the ECM data by following the prompts on the tester screen.
HINT:
The hand-held tester which has a "Snapshot" function which records the monitored data.
Please refer to the hand-held tester operator's manual for further details.
- DTC CLEARANCE
- The following actions will erase DTCs and freeze frame data.
- Operating the OBD II scan tool (complying with SAEJ1978) or hand-held tester to erase the codes (See the OBD II scan tool's instruction book for operating instructions).
- Disconnecting the battery terminals or EFI1 fuse.
- After completing repairs, the DTC retained in the memory can be cleared by removing the ECU-B fuse for 10 seconds or more with the ignition switch OFF.
- Check that the normal code is displayed after connecting the fuse.
- The following actions will erase DTCs and freeze frame data.
- PROBLEM SYMPTOM CONFIRMATION (Road Test)
- Inspect the SET switch.
- Push the main switch ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Push the control switch downward for SET/COAST.
- After releasing the switch, check that the vehicle cruises at the desired speed.
- Inspect the ACC (acceleration) switch.
- Push the main switch ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Check that the vehicle speed increases while the control switch is turned to RES/ACC, and that the vehicle cruises at the set speed when the switch is released.
- Momentarily push the control switch upward for RES/ACC and then immediately release it. Check that the vehicle speed increases by about 1.5 km/h (Tap-up function).
- Inspect the COAST switch.
- Push the main switch ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Check that the vehicle speed decreases while the control switch is turned to SET/COAST, and the vehicle cruises at the set speed when the switch is released.
- Momentarily push the control switch downward for SET/COAST, and then immediately release it. Check that the vehicle speed decreases by about 1.5 km/h (Tap-down function).
- Inspect the CANCEL switch.
- Push the main switch ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- When operating one of the followings, check that the cruise control system is cancelled and that the normal driving mode is reset.
- Depress the brake pedal.
- Shift into except S position.
- Push the main switch OFF.
- Pull the cruise control switch for CANCEL.
- Inspect the RES (resume) switch.
- Push the main switch ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- When operating one of the followings, check that the cruise control system is cancelled and that the normal driving mode is reset.
- Depress the brake pedal.
- Shift into except S position.
- Pull the cruise control switch for CANCEL.
- After the control switch is turned to RES/ACC at the driving speed of more than 40 km/h (25 mph), check that the vehicle restores the speed before the cancellation.
- Inspect the SET switch.
- INPUT SIGNAL CHECK BY USING HAND-HELD TESTER
- Connect the hand-held tester to the DLC3
- Check the control switch (CRUISE ON/OFF, CANCEL, SET/COAST, RES/ACC).