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TCS throttle body

TCS throttle body


The TCS throttle body consists of a body, butterfly, electric motor and linkage. It is mounted after the regular throttle body and cannot be fitted the wrong way round.

In Limp-Home mode there is no extra cable to regulate the TCS throttle butterfly. Instead, the power supply for the electric motor is switched off and the spring sets the butterfly to the wide open position.

Important

No adjustment must be made to the throttle butterfly.


The motor is a DC motor supplied with a 500 Hz PWM output from pins 18 and 35 of the control module. The motor can be run in both directions.

As a spare part, the TCS throttle body is replaced as a complete unit.

The TCS system is self-calibrating, see .

Information from the TCS throttle butterfly position sensor is received on pin 27 of the control module.

Depending on the position of the TCS throttle butterfly, the voltage will vary between about 1.1 and 4.4 V.

The position sensor is supplied with 5 V from pin 3 of the control module and grounded via pin 20.

On cars with automatic transmission the TCS control module sends a PWM signal from pin 4 giving the position of the throttle valve. The PWM signal is received by the transmission control module.

With the throttle valve closed the voltage is about 1.6 V and with the valve open about 8.5-11 V.




Power supply for the throttle actuator motor

The TCS throttle actuator motor is supplied with a 500 Hz PWM output from pins 18 and 35 of the control module. When the butterfly is closed the voltage across pins 18 and 35 is about 3.5 V.

Diagnostic trouble codes are generated, the TCS OFF lamp lights up and the system is rendered inoperative in the event of a mechanical or electrical fault in the actuator motor or position sensor, or in connecting leads.