Electronic Power Control (EPC) System, Checking

Electronic Power Control (EPC) System, Checking
(Engine Code: AVH, AZG)
Electronic Power Control EPC) system, function

In the EPC or "E-Gas" system, the throttle valve is not operated via a cable from the accelerator pedal. There is no mechanical connection between the accelerator pedal and the throttle valve.

The position of the accelerator pedal is communicated to the engine control module via two sensors for accelerator pedal position (changeable resistances; stored in one housing) that are connected with the accelerator pedal.

The position of the accelerator pedal (driver's intention) is a main input value for the Engine Control Module (ECM).

Operation of the throttle valve occurs throughout the entire RPM and load range via an electric motor (throttle valve actuator) in the throttle valve control module.

The throttle valve is operated by the throttle valve actuator according to the specifications of the Engine Control Module (ECM).

With the engine at standstill and the ignition switched on, the Engine Control Module (ECM) activates the throttle valve actuator exactly according to the specifications of the accelerator pedal position sensor. This means, if the pedal is depressed half way, the throttle valve actuator opens the throttle valve to the same degree; the throttle valve is then opened half way.

With the engine running (under load), the Engine Control Module can open and close the throttle valve independently of the accelerator pedal position sensor.

In this way, the throttle valve can already be completely open, even though the accelerator pedal has only been depressed half way. This is advantageous since charging losses at the throttle valve can be avoided.Furthermore, it results in significantly better emissions and consumption values under certain load conditions.

It would be wrong to assume that "E-Gas" consists of only one or two components. E-Gas is much more of a system containing all components that contribute to determining, regulating and monitoring the throttle valve position (e.g. accelerator pedal position sensor, throttle valve control module, Electronic Power Control (EPC) warning lamp, Engine Control Module (ECM))





Electronic Power Control (EPC) system, checking
(Engine Code: AVH, AZG)
1. Bracket
2. Connector
^ Black, 6 pin
3. 10 Nm
4. Throttle Position (TP) Sensor -G79
^ Not adjustable
^ Throttle position (TP) sensor-G79communicates the driver's intentions to the control module
^ To remove sensor, remove cover in footwell
^ Checking, Refer to Accelerator Pedal Position Sensor, Checking
^ If replaced adapt control module for automatic transmission
Refer to Powertrain Management
5. Bracket
^ For cover in footwell
^ Clipped on at accelerator pedal position sensor