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Brief description

Brief description

Saab Trionic T7 LEV is an engine management system that regulates air mass, fuel and ignition from the same control module.

LEV stands for “Low Emission Vehicle”, which means that the system meets the current regulations in each respective market. To meet these requirements for LEV, the integrity diagnosis has been changed. The requirement on the integrity diagnosis is to be able to detect a leak corresponding to a hole with a diameter of 1 mm. The control module is available in two configurations, the US/CA market and other markets. For those markets that do not have legal requirements for integrity diagnosis (other markets) are nonetheless equipped with the LEV integrity diagnosis. The difference between the control modules is that on markets without legal requirements, diagnostic trouble codes will be generated in case of a fault but the Check Engine lamp (MIL) will not come on.

When the driver depresses the accelerator pedal, the accelerator cable turns the pedal position sensor located in the throttle body. The system request a torque and the throttle motor turns the throttle until the throttle position sensor value corresponds to the requested torque. The system has the following advantages:


• Compensation for the turbo lag is possible.

• Exhaust emissions can be reduced in connection with load changes.

• The idle speed control is integrated.

• Load compensation is possible throughout the entire load and speed register.

• Effective torque limitation as necessary.

• Cruise control can easily be integrated.


Fuel injection is sequential and controlled by the mass air flow.

Ignition takes place by means of an ignition discharge module. The spark plugs act as sensors to detect combustion and knocking. This means that neither the camshaft position sensor nor the knock sensor are required.

The Saab Trionic T7 was developed by Saab and has huge development potential.

Compared with previous Trionic systems, the following functions are new:

Throttle body (604)


• Contains the pedal position sensor (which is turned by the throttle cable), throttle motor and throttle position sensor.

• Informs the control module of the driver's torque request.

• Turns the throttle to the position determined by the control module.


Limp-home solenoid (607)


• Supplied with current via the relay, the limp-home solenoid (640) is controlled by the control module.

• It provides a mechanical connection between the throttle cable and the throttle spindle if a fault occurs in the throttle body or its leads. The mechanism must be reset manually.


Charge air absolute pressure sensor (603)


• Informs the control module of the pressure level before the throttle.

• Used to determine the density of the air before the throttle.


Dense air requires a smaller throttle angle.

Intake air temperature sensor (407)


• Informs the control module of the temperature before the throttle.

• Used to determine the density of the air before the throttle.


Dense air requires a smaller throttle angle.

Manifold absolute pressure sensor (431)


• Informs the control module of the pressure level after the throttle.

• Used to correct the mass air flow sensor value when rapid load changes occur.


Mass air flow sensor (205)


• Sends frequency-modulated information on the mass air flow to the control module.

• Acts as a main sensor for fuel injection.