warning AUDI TT 1995 8N / 1.G ATW Engine Electronic Power Control Checking Workshop Manual

24-114
With engine running (under load), the ECM can
open or close the throttle valve independently of
the sensor for accelerator pedal position.
This means, for example, that the throttle valve
could be fully opened even though the
accelerator pedal has only been depressed half
way. This has the advantage of preventing
torque losses at the throttle valve.
In addition to this, it results in significantly better
values relative to emissions and consumption
under certain load conditions.
The required engine torque can be achieved by
the Engine Control Module (ECM) via the optimal
combination of throttle valve diameter and boost
pressure.
It would be incorrect to think that "E-Gas"
consists of only one or two component. E-Gas is
much more of a system containing all
components that contribute to recognizing,
controlling and monitoring the position of the
throttle valve, e.g. sensor for accelerator pedal
position, throttle valve control module, EPC
warning lamp, Engine Control Module (ECM).
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24-115

Electronic Power Control (EPC) warning
lamp in instrument cluster


Note:
The Electronic Power Control (EPC) warning
lamp -K132- is also called the fault light for power
accelerator activation.
"EPC" is an abbreviation and stands for
Electronic Power Control (E-gas).

Installation location of EPC warning lamp
Engine Control Module (ECM) checks all components that are important
for function of the E-Gas system after ignition is switched on.
The Engine Control Module (ECM) switches on the EPC warning lamp
after ignition is switched on. Shortly after engine is started, the EPC
warning lamp will go out. This requires, first of all, that the Engine Control
Module (ECM) does not detect a malfunction in the E-gas system and,
secondly, that activation of the lamp by the Engine Control Module (ECM)
is OK.
If malfunctions are recognized in the E-Gas system during operation of
the engine, the ECM switches on the EPC warning lamp in instrument
cluster. (These malfunctions are listed in the DTC table). An entry is made
in DTC memory at the same time.
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24-116

Electronic Power Control (EPC) warning
lamp -K132-, checking


Note:
The fault light for power accelerator activation -
K132- is also called the EPC warning lamp.

Special tools and equipment

VAG1594A

VAG1598/31
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24-117

Function test of warning lamp

- Switch ignition on.


The EPC warning lamp must light up for
approximately 3 seconds if there are no
malfunctions stored in DTC memory that
relate to the E-gas system

A- Fault light for power accelerator activation
-K132- does not light up

- Connect VAG1598/31 test box at wiring harness
to Engine Control Module (ECM), do not connect
ECM Page 24
-19
.

- Bridge terminals 1 and 48 at test box using wires
from VAG1594A adapter test kit.

- Switch ignition on.


Warning lamp must light up.
If warning lamp does not light up:

- Switch ignition off.

- Remove instrument cluster:
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ge 6 of 51 Electronic En
gine Power Control
(EPC
) (E-Gas
), checkin
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU06.24.4