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Trionic

Trionic

Description of operation

Trionic is an engine management system in which fuel injection, ignition timing and boost pressure regulation are integrated in a single system with a common control module. There are many similarities between Trionic and LH and DI/APC, but Trionic has a number of new components and functions. The most important electrical changes when compared with the earlier LH and DI/APC system are as follows:


• One control module instead of two

• Mass air flow sensor 205 has been replaced with a sensor that measures the pressure in the intake manifold 431, and an intake air temperature sensor 407.

• Knock sensor 178 has been replaced with an integrated knock sensor function (ionization measurement) in a new ignition discharge module 346.


Trionic control module

Control module 430 monitors and controls a number of functions.

The control module receives information from:




• Ignition switch 20

• Brake lights switch 29

• Cruise control module 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

• Air temperature sensor 407

• Pressure sensor 431

• ICE control module 500 (radiator fan)


The control module sends information to:




• SHIFT UP indicator lamp 47K

• CHECK ENGINE indicator 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 valve 272

• EVAP canister purge valve 321

• Ignition discharge module 346

• Data link connector 445

• Main Instrument Unit 540B


Power supply

The system is supplied with a positive voltage, from fuse 17 when the ignition switch is in the start or drive position, and a constant +30 voltage to relays 229 and 102, and the Trionic control module 430.

Fuel supply

Fuel supply is maintained by fuel pump 323 creating a fuel pressure in the system.

The fuel function is adaptive, which means that the fuel supply is constantly suited to any wear or change in components, etc.

Ignition timing

The program for ignition time is static and cannot be adjusted. The timing is retarded in the event of:


• knock indication

• fuel shut-off

(engine braking with closed throttle).


Data link connector 445

The data link connector for connection to ISAT is positioned beneath the dashboard by the steering wheel (16-pin connector).

Sparkplug burn-off

The sparkplugs are burnt off automatically every time the engine is switched off with the ignition key. All plugs are burnt off simultaneously for 5 seconds at a rate of 210 sparks per second.

Important

Power to the Trionic control module and ignition discharge module is taken from the main relay of the engine management system, which is closed for 6 seconds after the engine has been switched off with the ignition key.


SHIFT UP indicator 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 lamp 47K in the main instrument unit, which comes on when an upshift should be made, i.e. when engine speed and throttle opening reach certain values. When the engine load drops below a certain level (basic injection time) and engine speed reaches certain values, the control module grounds lamp 47K via pin 55.

Cars with automatic transmission TCM

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

Tachometer 110

Tachometer 110 in the main instrument unit 540 is supplied with current via fuse 17. Control pulses are received from control module 430 to show engine speed.

Turbo pressure gauge 558

Control module 430 sends a signal, proportional to the intake manifold pressure, to the main instrument unit control module 540. The MIU controls the turbo pressure gauge based on this signal. The turbo pressure gauge is supplied with +15 voltage via fuse 17.

Exhaust emission control, Lambda

This 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 heating element 271 and fused by fuse 38.

Boost pressure control valve 179

The boost pressure control valve controls the turbo's boost pressure via signals from the control module. Signals from the sensors and from the ignition system are continuously fed to the control module and on the basis of these signals the control module actuates the boost pressure control valve and thus controls 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 is possible to ignore the setting tolerances that 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 the antifrost thermostat 171 that the A/C system is engaged. The control module grounds the 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 the signal, the control module simulates a temperature of 26 °C.

Throttle position sensor 203

Throttle position sensors 203 provides the control module with information on the position of the throttle butterfly valve. The sensor provides information about all angles, from idling to fully open.

CHECK ENGINE lamp 47O

The CHECK ENGINE lamp in the main instrument unit 540 lights up when a serious fault arises in the system.

Idle air control valve 272

The idle air control valve (IACV) is regulated by means of current variations from the Trionic control module. The control module regulates the valve's position 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 somewhat like a small alternator, the sinusoidal voltage and frequency of which is proportional to engine speed. 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 speed and identify the cylinders in which the pistons are at or approaching TDC. If the sensor does not work due to a break in the circuit, for example, the engine will not start.

Ignition discharge module 346

The ignition discharge module incorporates a transformer with increase 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

Risk of burns!

Although the system voltage is only 12 V, there is still a risk of burns or fire in the car, since the energy content of the battery is very high. A short circuit could give rise to extremely high currents!

Warning - high tension!

The electronic ignition system generates voltages in excess of 48,000 volts. This voltage can be lethal. Therefore, always turn off the ignition before touching the ignition system components.


Air temperature sensor 407

The air temperature sensor is located on the intake manifold and is of the NTC type. It 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 pressure sensor 431) and the temperature of the intake air, the current air mass can be determined.

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 as a voltage pulse. Low pressure=Low voltage. High pressure=High voltage. On the basis of information about the current air pressure and air temperature (from temperature sensor 407), the current air mass can be determined.