Section 493 (Cruise Control System - Diagnostics): Pre-Check
- DIAGNOSIS SYSTEM
- Description
ECM controls the function of the cruise control on a vehicle.
Data on the cruise control and on the DTC can be read from the DLC3 on the vehicle. If CRUISE MAIN indicator light does not comes on after the DTC check, there is a malfunction on the cruise control.
Use the hand-held tester or SST to check and solve the problem.
- Check the DLC3.
The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
SPECIFIED CONNECTION CONDITIONTerminal No. Connection/Specified Condition Condition 4 Chassis Ground <-> Body Ground / 1 Ω or less Always 7 Bus oplus Line / Pulse Generation During Communication 16 Battery Positive <-> Body Ground / 9 - 14 V Always HINT:
If the display shows "UNABLE TO CONNECT TO VEHICLE" as connecting the hand-held tester to the DLC3 and turn the ignition ON, there is a problem either on the vehicle or on the tool.
- If communication is normal when connecting the tool to another vehicle, inspect DLC3 on the original vehicle.
- If communication is still not possible when connecting the tool to another vehicle, the problem is probably in the tool itself. Consult the Service Department listed in the tool's instruction manual in that case.
- Check the indicator.
- Turn the ignition switch to ON.
- Check that the CRUISE MAIN indicator light comes on when the main switch button 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 HOW TO PROCEED WITH TROUBLESHOOTING ) for the combination meter section.
- Check the DTC.
HINT:
If a malfunction occurs in the vehicle speed sensors or stop lamp switch assy, etc. during cruise control driving, the ECU 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 memory as a diagnostic trouble code.
- Output of DTC using diagnosis check wire.
- Turn the ignition switch to ON.
- Using SST, connect terminals TC and CG of DLC3.
SST 09843-18040
- Read the DTC on the CRUISE MAIN indicator light.
HINT:
If the DTC is not output, inspect the cruise main indicator light circuit (See CRUISE MAIN INDICATOR LIGHT CIRCUIT ).
As an example, the blinking patterns for codes; normal, 52 are shown in the illustration.
- Description
- USING HAND-HELD TESTER
- Hook up the hand-held tester to the DLC3.
- Monitor the ECU data by following the prompts on the tester screen.
HINT:
Hand-held tester has a "Snapshot" function which records the monitored data.
Please refer to the hand-held tester operator's manual for further details.
- DATA LIST
HINT:
According to the DATA LIST displayed on the hand-held tester, you can read the value of the switch, the sensor and so on without removing parts. Reading the DATA LIST as a first step of troubleshooting is one of the method to shorten the labor time.
- Connect the hand-held tester to the DLC3.
- Turn the ignition switch to ON.
- According to the display on tester, read the "DATA LIST".
HINT:
"3" is OK but "1" is NG --> ECM failure
"1" is OK but "2" is NG --> DTC output or ECM failure
"3" is OK but cruise indicator not turn on --> CRUISE MAIN indicator or wire harness or ECM failure
- DTC CLEAR
- The following actions will erase the DTCs and freeze frame data.
- Hand-Held Tester:
Operating the hand-held tester to erase the codes.
- Except Hand-Held Tester:
Disconnecting the battery terminals or EFI fuse.
- Hand-Held Tester:
- After completing repairs, the DTC retained in memory can be cleared by removing the EFI fuse for 1 minutes or more with the ignition switch OFF.
- Check that the normal code is displayed after connecting the fuse.
- The following actions will erase the DTCs and freeze frame data.
- PROBLEM SYMPTOM CONFIRMATION (ROAD TEST)
- Inspect the SET switch.
- Push the main switch button to ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Push down the control switch to the -/SET.
- After releasing the switch, check that the vehicle cruises at the desired speed.
- Inspect the '+' switch.
- Push the main switch button to ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Check that the vehicle speed increases while the control switch is pull up to +/RES, and that the vehicle cruises at the set speed when the switch is released.
- Momentarily push the control switch upward to the +/RES, and then immediately release it. Check that the vehicle speed increases by about 1.5 km/h (Tap-up function).
- Inspect the '-' switch.
- Push the main switch button to ON.
- Drive at a desired speed (40 km/h (25 mph) or higher).
- Check that the vehicle speed decreases while the control switch is push down to -/SET, and the vehicle cruises at the set speed when the switch is released.
- Momentarily push the control switch downward to -/SET, 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 button to 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 to except D position.
- Push the main switch button to OFF.
- Pull the control switch to CANCEL.
- Inspect the RES switch.
- Push the main switch button to 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 to except D position.
- Pull the control switch to CANCEL.
- After the control switch is pull up to +/RES 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.