Volkswagen Phaeton 2003, Workshop Manual

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3 Checking electronic power control (EPC)
1 - Mounting bracket
❑ Removing and instal‐
ling: ⇒ Brake systems;
Rep. gr. 46 ; Assembly
overview - brake pedal
(LHD) .
2 - Connector
❑ Black, 6-pin.
3 - 10 Nm
4 - Accelerator position sender
- G79- and accelerator position
sender 2 - G185-
❑ Not adjustable.
❑ Remove footwell cover
to remove sender.
Function of EPC system
With the EPC system, the throttle valve is not operated by a cable
from the accelerator There is no mechanical connection between
the accelerator and the throttle valve.
The position of the accelerator is transmitted to the engine control
unit by two accelerator position senders (variable resistors to‐
gether in one housing) connected to the accelerator.
The position of the accelerator (driver's requirement) is a main
input value for the engine control unit.
The throttle valve is operated over the complete engine speed
and load range by an electric motor (throttle valve positioner) in
the throttle valve module.
The throttle valve is operated by the throttle valve positioner which
is controlled by the engine control unit.
When the engine is not running and the ignition is switched on,
the engine control unit moves the throttle valve exactly as pre‐
scribed by the accelerator position sender. That is, when the
accelerator is depressed halfway, the throttle valve positioner
Phaeton 2003 ➤
6-cylinder injection engine - Edition 02.2014
3. Checking electronic power control (EPC)
153