1-9 THS (TOYOTA HYBRID SYSTEM)
(2) When any of the conditions described below is present, the message prompt as shown appears in the multi center display, accompanied by the illumination of the master warning light and the continuous sounding of the buzzer.
A. The READY light is illuminated, the shift lever is in the N position, and the HV battery is discharged.
B. The READY light is illuminated, the shift lever is in the N position, and the driver' door is open.
C. The READY light is illuminated, the parking brake is engaged, the shift lever is in the B or D position, and the driver's door is open.
- MOTOR AND GENERATOR
OUTLINE
· Both the electric motor and the generator are the compact, lightweight, and highly efficient alternating current synchronous type.
· Serving as the source of supplemental motive force that provides power assist to the output of the engine as needed, the electric motor helps the vehicle achieve an excellent dynamic performance that includes smooth start-offs and acceleration. When the regenerative brake is activated, the electric motor converts the vehicle's kinetic energy into electrical energy, which is then stored in the HV battery.
· The generator recharges the HV battery and supplies electrical power to drive the electric motor. In addition, by regulating the amount of electrical power generated, thus varying the generator's rpm, the generator effectively controls the stepless transmission function of the transaxle. The generator also serves as the starter to start the engine.
(1) Specifications
Electric Motor Type 1CM Rated voltage [V] 288 Maximum output [kW] (rpm) 30.0/(940-2000) Amperage at maximum torque [Al 351 Cooling system Water-cooled
Maximum torque [N.m (kgf. m) (rpm)
305{31.1}/(0-940)



2-2 ENGINE -- 1NZ-FXE ENGINE
2-1 1NZ-FXE ENGINE
The Prius uses the 1NZ-FXE, a 1.5-liter gasoline engine that has been newly developed for hybrid system application. It is an inline 4-cylinder, chain-driven 4-valve (2 intake and 2 exhaust valves per cylinder) DOHC engine. This engine has adopted the VVT-i (Variable Valve Timing-intelligent) system, the high-expansion ratio Atkinson cycle, the offset crankshaft, and the use of two 02 sensors. In addition, weight reduction and low-friction measures have been applied to its moving parts in order to achieve an extremely low fuel consumption rate, low exhaust emissions, weight reduction, a compact shape, low vibrations, and low noise levels. This engine complies with the "1998 Exhaust Gas Emission Regulations".
Furthermore, this engine offers excellent engine control and serviceability through the adoption of the following features: TCCS (Toyota Computer Controlled System, a comprehensive engine control system), KCS (Knock Control System), TDI (Toyota Direct Ignition System), and new diagnostic functions.

Engine Specifications
| 1NZ-FXE | |||
| Cylinder displacement [L] | 1.496 | ||
| Number of cylinders and arrangement | Inline 4-cylinder, transversely mounted | ||
| Combustion
chamber shape |
Pentroof
shape (oblique squish) |
||
| Number
of intake/exhaust valves per cylinder |
2 each |
||
| Valvetrain | DOHC, chain-driven | ||
Fuel supply system |
EFI
(Electronic Fuel Injection) |
||
| Bore x stroke [mm] | 75.0X84.7 | ||
| Compression ratio | 13.5 | ||
| Maximum
power output <net> [kW (PS)] (rpm) |
42.7{58} (4000) |
||
| Maximum
torque <net> [N.m (kgf. m)] (rpm) |
102{10.4} (4000) |
||
| Fuel
consumption rate [g/kW.h (g/PS.h)] (rpm) |
245{180} (2800) |
||
| Dimensions
[mm] <Length x Width x Height> |
560X595×680 |
||
| Valve timing | Intake |
Open | --30~10° BTDC*1 |
| Close | 120~80° ABDC*1 | ||
| Exhaust | Open | 32° BBDC | |
| Close | 2° ATDC | ||
| Firing order | 1-3-4-2 | ||
| Reference
engine service weight [kg] |
88.3*2 |
||
| Fuel used | Unleaded regular gasoline | ||
| Oil used (ex-factory) | SAE5W-20, APl SJ | ||
*1: Due to the adoption of the VVT-i (Variable Valve Timing-intelligent) system.
*2: Engine service weight including coolant, oil, and air cleaner.
2-32 ENGINE -- 1NZ-FXE ENGINE
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- Engine Electrical System
1. TDI (Toyota Direct Ignition System: ignition coil with built-in igniter)
- The TDI system has been adopted for improved precision of ignition timing control, and ignition timing that is completely free of adjustments.
- Ultra-compact cylindrical ignition coils have been adopted. Shaped to enable each of the coils to be independently connected directly to the spark plugs for the cylinders, the coils are placed in the plug holes in the cylinder head. Consequently, the use of high-tension cords is made unnecessary, thus minimizing high-voltage loss and electromagnetic interference.

2-35 ENGINE -- 1NZ-FXE ENGINE
- Engine Control System
1. Overview
Along with the adoption of the hybrid system, the EFI control and single-valve electronic throttle control functions have been integrated in the engine control computer. The functions of these controls remain basically the same as those of the vehicles with the conventional engine.
A characteristic of this engine control computer is that the engine's fuel injection control and throttle control are executed in accordance with the engine output command factors that are received through serial communication from the hybrid vehicle control computer.
2. System Configuration
The diagram shown below briefly describes the configuration that surrounds the engine control computer.
