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Trionic

Trionic

Principle of operation

The Trionic is an engine management system in which fuel injection, ignition and boost pressure control are integrated into a single system with a common control module. The Trionic on the one hand and LH and DI/APC on the other are very similar but the Trionic incorporates a number of new components and functions. The most important electrical changes compared to the earlier LH-DI/APC system are as follows:


• One control module instead of two.

• Mass air flow sensor 205 is replaced by a sensor for measuring the pressure in intake manifold 431 and intake air temperature sensor 407.

• Knock sensor 178 is replaced by a knock sensor function (ionization measurement) integrated into a new ignition discharge module (346).


TRIONIC control module

Control module 430 monitors and controls a number of functions.

The control module obtains information from:




• Ignition switch 20

• Brake light switch 29

• Control module, Cruise Control 508

• ABS control module 547

• Oxygen sensor 136

• Antifrost thermostat 171

• Engine coolant temperature sensor 202

• Throttle position sensor 203

• Crankshaft position sensor 345

• Ignition discharge module 346

• Intake air temperature sensor 407

• Manifold absolute pressure sensor 431

• ICE control module 500 (radiator fan)


The control module sends information to:




• SHIFT UP indicator lamp 47K

• Malfunction indicator (CHECK ENGINE) lamp 47O

• Fuel pump relay 102

• A/C compressor relay 156 (via pressure switch 166)

• Boost pressure control valve 179

• Injectors 206

• Main relay 229

• Oxygen sensor preheating element 271

• Idle air control (IAC) valve 272

• Canister purge valve 321

• Ignition discharge module 346

• Data link connector 445

• Main instrument display panel 540B


Power supply

The system is supplied with positive voltage via fuse 17 when the ignition switch is in the Start or Drive position. A constant voltage (+30 circuit) is also applied to relays 229 and 102 as well as Trionic control module 430.

Fuel supply

Fuel is supplied through fuel pump 323 building up pressure in the system.

The fuel supply function is adaptive, which means that the supply of fuel is continually adapted to any wear, changes in components, etc. that may occur.

Ignition timing

The ignition timing is programmed once and for all and there is no provision for adjustment. Retarded ignition (later spark) will be obtained in the following cases:


• knock indication

• fuel shut-off

(engine braking with closed throttle).


Data link connector 445

The data link connector for connection of an ISAT Scan Tool is located under the dashboard adjacent to the steering wheel (16-pin connector).

Spark plug burn-off

Automatic spark plug burn-off is carried out with a burst of sparks each time the engine is switched off. Burn-off is carried out in all cylinders simultaneously and lasts for 5 seconds at a rate of 210 sparks per second.

Important

Current for the Trionic control module and ignition discharge module is obtained from the main relay of the engine management system, which remains operated for 6 seconds after the engine has been switched off.


Upshift indication 47K

Shift-up indication is provided on cars with a manual gearbox for the US and CA markets. The system helps the driver to utilize the characteristics of the engine to best advantage and so obtain the lowest possible fuel consumption. This is done by means of the lamp (47K) in the main instrument unit which comes on when an upshift should be performed, i.e. when engine rpm and throttle opening reach certain values. When the engine load drops below a certain value (the basic injection time) and engine rpm reaches certain values, the control module grounds lamp 47K via pin 55.

Cars with automatic transmission, TCM

When the selector lever is moved to a position other than P or N, the Trionic control module receives a signal from the TCM control module to compensate for the load increase.

Tachometer 110

Tachometer 110 in main instrument display panel 540 is supplied with current via fuse 17. Control pulses are obtained from control module 430 to show engine rpm.

Turbo pressure gauge 558

Control module 430 sends a signal, proportional to the intake manifold pressure, to main instrument display control module 540. On the basis of this signal the main instrument display causes the turbo pressure gauge to give an indication. The turbo pressure gauge is supplied with +15 voltage via fuse 17.

Exhaust emission control, Lambda

The system is connected to an adaptive Lambda system which compensates for changes in the fuel-air mixture due to changes in the fuel system. Since oxygen sensor 136 continuously measures the oxygen content of the exhaust emissions, the control module can adjust the fuel-air mixture until it is as close as possible to lambda = 1. The sensor is heated by preheater 271, which is protected by fuse 38.

Boost pressure control valve 179

As its name implies, the boost pressure control valve controls the turbo's boost pressure via signals from the control module. Signals from the sensors and the ignition system are supplied continuously to the control module and on the basis of these signals it actuates the boost pressure control valve and thus the turbo's boost pressure. Since boost pressure is continuously adapted to the octane rating of the fuel and the engine's working conditions, it has been possible to ignore the setting tolerances which must normally be taken into account to avoid damaging the engine. As a result, the fuel currently consumed by the engine can be utilized to the full.

Air conditioning, A/C

The TRIONIC control module receives information from anti-frost thermostat 171 that the A/C system is engaged. The control module then grounds A/C relay 156 via pressure switch 166. When the A/C compressor is in operation the control module adjusts idling speed to compensate for the increased load on the engine.

Coolant temperature sensor 202

Coolant temperature sensor 202 is of NTC type and provides the control module with information on the temperature of the coolant. In the event of a break in this signal the control module simulates a temperature of 26°C.

Throttle position sensor 203

Throttle position sensor 203 provides the control module with information on the position of the throttle butterfly valve. The sensor gives the angle continuously from idling speed to wide open throttle.

Malfunction indicator (CHECK ENGINE) lamp 47O

The malfunction indicator (CHECK ENGINE) lamp in main instrument display panel 540 lights up when a serious fault arises in the system.

Idle air control (IAC) valve 272

The idle air control valve is regulated by means of current variations from the TRIONIC control module. The control module regulates the valve's degree of opening so that a controlled flow of air is allowed to pass the throttle butterfly. If the valve develops a fault, it will be automatically adjusted to a fixed idling speed of about 1200 rpm.

EVAP canister purge valve 321

The purge valve, mounted on the evaporative emission canister, is opened and closed by the control module.

Crankshaft position sensor 345

The control module receives information on the position and speed of the crankshaft from the crankshaft position sensor. The sensor consists of a slotted ring on the flywheel end of the crankshaft and an inductive sensor mounted in the engine block. The inductive sensor works somewehat like a small alternator, the sinusoidal voltage and frequency of which increase with increasing engine rpm. The sinusoidal voltage alternates between positive and negative potential. This is achieved by means of "teeth" on the slotted ring. This alternating polarity is utilized by the control module to determine engine rpm and identify the pair of cylinders in which the pistons are at or approaching TDC. If the sensor does not work because of a break in the circuit, for example, the engine will not start.

Ignition discharge module 346

The ignition discharge module incorporates a transformer which increases the voltage to 400 V, a capacitor in which the voltage is stored, integrated ignition coils (not replaceable) and a built-in knock sensing function.

Warning

The electronic ignition system generates voltages higher than 40,000 V. Such voltages may be fatal to persons with a weak heart or those who have a pacemaker. So treat the entire ignition system with great respect.


Temperature sensor 407

The temperature sensor is located in the intake manifold. It is of NTC type and provides the control module with a continuous signal containing information on the temperature of the intake air.

Low temperature = High voltage

High temperature = Low voltage

On the basis of the current air pressure (from manifold absolute pressure sensor 431) and the temperature of the intake air, the current air mass can be determined.

Manifold absolute pressure sensor 431

The Trionic system includes pressure sensor 431 which continuously senses the pressure in the intake manifold. The pressure sensor sends this information to the Trionic control module in the form of a voltage pulse. Low pressure = Low voltage, High pressure = High voltage. On the basis of information on the current air pressure and temperature (from temperature sensor 407) in the intake manifold, the current air mass can be determined.