Engine Setup - 95 My; Throttle Sensor Adjustment - 95 My - Aston Martin DB7 Workshop Manual

The Aston Martin Lagonda Diagnostic System
Users Guide
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Engine Setup - 95 MY
Two adjustments may beset with the aid of the PDU on 95
MY vehicles.
• Throttle Potentiometer
• Idle Fuelling Trim
From the 95 MY Main Menu, make and confirm the
following sequence of selections:
Diagnostics /
Manual or Auto Transmission /
Engine /
Engine Setup /
The following connection diagram w i l l then be displayed.
Throttle Sensor Adjustment - 95 MY
Note: The throttle stop and throttle cable adjustments
must be correct before setting the throttle potentiometer.
On completion of the engine setup connections the test
selection screen will be displayed.
1. Select Throttle Potentiometer.
2. Turn the ignition switch to position II but do not
start the engine.
3. Monitorthethrottle potentiometer bargraph voltage
at fully closed and then at fully open throttle.
4. The throttle potentiometer voltage specifications
are:
Throttle Closed 0.57 - 0.59V
Throttle Full Open 4.00 +V
Cable Setup
Diagnostic Socket
D
Engine Setup Connections
Tinrottle Position Sensor
Value : 0.43V
570 600
Idle Voltage (mV)
Make adjustments as
necessary
Throttle Potentiometer Voltage
5. If both voltages are either high or low, loosen the
two throttle pot screws and adjust the potentiometer
until the specified voltages are achieved. Carefully
tighten both screws ensuringthat the potentiometer
does not move during tightening.
6. If either voltage is unstable or if the specified
voltages cannot be achieved, investigate the cause.
If the potentiometer is replaced, set the new pot
using steps 3 - 5 above.
Note: On automatic vehicles, the kickdown switch
adjustment check follows the throttle pot adjustment.
9-38
September 1996