DESCRIPTION
The speed sensor detects the wheel speed and sends the appropriate signals to the master cylinder solenoid (skid control ECU). The master cylinder solenoid (skid control ECU) converts these wheel speed signals into a 4-pulse signal and outputs it to the ECM via the combination meter. The ECM determines the vehicle speed based on the frequency of these pulse signals.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0500 | The vehicle speed signal from the vehicle speed sensor is cut for 0.14 sec. or more while cruise control is in operation. | Vehicle speed sensor signal circuit Vehicle speed sensor Combination meter ECM |
Scheme 13
If a malfunction (a rapid change in vehicle speed) in the vehicle speed signal being output from the master cylinder solenoid (skid control ECU) is detected while the cruise control is in operation, the ECM determines there to be a momentary interruption and noise, and outputs a DTC.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0503 | A momentary interruption and noise are detected when a rapid change of the vehicle speed occurs while cruise control is in operation. | Vehicle speed sensor Vehicle speed sensor signal circuit ECM Combination meter |
When the brake pedal is depressed, the stop light switch sends a signal to the ECM. When the ECM receives this signal, it cancels the cruise control. The fail-safe function operates to enable normal driving even if there is a malfunction in the stop light signal circuit. The cancellation condition occurs when voltage is applied to terminal STP. When the brake is applied, voltage is applied to terminal STP of the ECM through the STOP fuse and the stop light switch, and the ECM turns the cruise control off.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0571 | When the voltage of the STP terminal and the ST1- terminal of the ECM is below 1 V for 0.5 sec. or more. | Stop light switch Stop light switch circuit ECM |
Scheme 14
This DTC indicates internal abnormalities of the ECM.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0575 | When either of the following conditions is met: STP signals input to the ECM supervisory CPU and control ECU are different for 0.15 seconds or more. 0.4 seconds have passed after the cruise cancel input signal (STP input) is input to the ECM. | ECM |
HINT
If DTC P0575 is stored while the cruise control is in operation, the master cylinder solenoid (skid control ECU) clears the stored vehicle speed in the ECM and cancels the cruise control operation. At the same time, the CRUISE main indicator light blinks to inform the driver of the malfunction. When this trouble code is stored, fail-safe remains on until the engine switch is turned off.
The cruise control main switch is used to operate 7 functions: SET, - (COAST), TAP-DOWN, RES (RESUME), + (ACCELERATION), TAP-UP, and CANCEL. The SET, TAP-DOWN and - (COAST) functions, and the RES (RESUME), TAP-UP and + (ACCELERATION) functions are operated with the same switch. The cruise control main switch is an automatic return type switch which turns on only while operating it in each arrow direction and turns off after releasing it. The internal contact point of the cruise control main switch is turned on with the switch operation. Then the ECM reads the resistance value that has been changed by the switch operation to control SET, - (COAST), RES (RESUME), + (ACCELERATION) and CANCEL.
Scheme 15
- The ECM detects a cruise control switch signal and sends it to the combination meter via the CAN communication line. Then the cruise control indicator light comes on.
- The cruise control indicator light circuit uses the CAN for communication. If there is a malfunction in this circuit, check for DTCs in the CAN communication system before troubleshooting this circuit.
Scheme 16
- When the ECM detects a cruise control switch on signal from the cruise control switch, it sends it to the combination meter assembly through CAN communication. Then the cruise control SET indicator light turns on.
- The cruise control SET indicator light circuit uses CAN communication. If there is a malfunction in this circuit, check for DTCs in the CAN communication system before troubleshooting this circuit.
Connecting terminals TC and CG of the DLC3 causes the system to enter self-diagnostic mode. If a malfunction is present, DTCs will be output.
HINT
When a particular warning light remains blinking, a ground short in the wiring of terminal TC of the DLC3 or an internal ground short in the relevant ECU is suspected.
