Smart Access System With Push-Button Start (for Start Function)
THEFT DETERRENT / KEYLESS ENTRY: SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function): SYSTEM DIAGRAM
Communication Table
THEFT DETERRENT / KEYLESS ENTRY: SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function): SYSTEM DESCRIPTION
1. PUSH-BUTTON START DESCRIPTION
(a) The push-button start uses a push-type power switch, which the driver can operate by merely carrying the electrical key. This system consists primarily of the power management control ECU, power switch, transmission control ECU assembly, electrical key, ACC relay, P/POINT relay, IG1 NO. 1 relay, IG1 NO. 2 relay, IG1 NO. 3 relay, IG2 relay, ID code box (immobilizer code ECU) and certification ECU (smart key ECU assembly). The power management control ECU controls the system. This function operates in cooperation with the smart access system with push-button start.
HINT
In this chapter, the expression "power source" has been used in some locations to allow precise explanations. The power source mode is also expressed using conventional expressions such as "power switch off", "power switch on (ACC)" and "power switch on (IG)".
2. FUNCTION OF MAIN COMPONENTS
3. SYSTEM FUNCTION
The electric controls of the push-button start function are described below:
4. CONSTRUCTION AND OPERATION
(a) Power Switch
The power switch consists of a momentary type switch, 3 color (amber, green, greenish white) LEDs, and a transponder key amplifier.
* The greenish white LED is for illumination.
* The amber and green LEDs are for the indicator lights. The driver can check the present power source mode and whether the hybrid control system can start in accordance with the illumination state of the indicator light.
* When the power management control ECU detects an abnormality in the push-button start system, it makes the amber indicator light flash. If the hybrid control system stopped in this state, it may not be possible to restart it.
(b) Indicator Light Condition
Power Switch Indicator Light Condition
(c) Power Management Control ECU
The power management control ECU consists of the IG1 NO. 1, IG1 NO. 2, IG1 NO. 3, IG2, ACC, P/POINT relay actuation circuits and CPU.
HINT
Before removing the auxiliary battery, make sure to turn the power switch off. The power management control ECU constantly stores the present power source mode in its memory. Therefore, if the power supply for the power management control ECU is interrupted by disconnecting the auxiliary battery, the power management control ECU restores the power source mode after the auxiliary battery is reconnected. For this reason, if the auxiliary battery is disconnected when the power switch is other than off, the power source mode will be restored to the vehicle at the same time the power source mode is restored to the power management control ECU (by reconnecting the auxiliary battery).
5. PUSH-BUTTON START FUNCTION OPERATION
(a) This system has different power source mode patterns depending on the brake pedal condition and state.
(a) When the key battery is low, the push-button start function can be operated by holding the key against the power switch.
* After approximately 1 hour has elapsed with the power switch on (ACC) or on (IG) and park (P) selected, the power management control ECU will automatically cut the power supply (the power source mode will change to off).
* The illustration below shows the transition of power source modes.
* Transition of power source modes:
HINT
While the vehicle is being driven normally, operation of the power switch is disabled. However, if the hybrid control system must be stopped in an emergency while the vehicle is being driven, pressing the power switch for 3 seconds or more stops the hybrid control system. The power source mode will change from on (READY) to on (ACC).
6. WHEN KEY BATTERY IS LOW
(a) To operate the push-button start function when the key battery is low, hold the key close to the power switch with the brake pedal depressed.
(b) The power management control ECU transmits a key verification request signal to the certification ECU (smart key ECU assembly) when it receives the stop light switch signal.
(c) The certification ECU (smart key ECU assembly) does not receive an ID code response from the entry door control receiver, so it actuates the transponder key amplifier built into the power switch.
(d) The transponder key amplifier outputs an engine immobilizer radio wave to the key.
(e) The key receives the radio wave, and returns a radio wave response to the transponder key amplifier.
(f) The transponder key amplifier combines the key ID codes with the radio wave response, and transmits it to the certification ECU (smart key ECU assembly).
(g) The certification ECU (smart key ECU assembly) judges and verifies the ID code, and transmits a key verification OK signal to the power management control ECU. The buzzer in the combination meter assembly sounds at the same time.
(h) After the buzzer sounds, if the power switch is pressed within 10 seconds with the brake pedal not depressed, the power source mode changes to on (ACC) or on (IG), the same as in the normal condition.
HINT
The key (for card type) operation inspection can be performed using the same procedure as for the key (for standard type).
7. DIAGNOSIS
The power management control ECU can detect malfunctions in the push-button start function when the power source mode is on (IG).
When the ECU detects a malfunction, the amber indicator light of the power switch flashes to warn the driver. At the same time, the ECU stores a 5-digit Diagnostic Trouble Code (DTC) in its memory.
* The indicator light warning continues for 15 seconds even after the power source mode is changed to off.
* The DTC can be read by connecting the Techstream to the DLC3.
* The push-button start function cannot be operated if a malfunction occurs.