Throttle position information sent to theTCS and AF22 control modules
Symptom: Diagnostic trouble code P1785 generated in the AF22 control module
or one of the diagnostic trouble codes P1406, P1407 or P1408 generated
in the TCS control module.
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Throttle position information sent to the
TCS and AF22 control modules
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Fault symptom
Diagnostic trouble code P1785 generated in the AF22 control module
or one of the diagnostic trouble codes P1406, P1407 or P1408 generated
in the TCS control module.
1.
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Use the ISAT command
"THROTTLE POSITION" in the "READ
FUNCTIONS" menu and, with the ignition switch in the Drive position,
check whether the ISAT shows about 9%%in the idling position and
steadily increases to 85-90%% in the full throttle position.
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2.
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With the ignition switched off, connect a BOB between the MOTRONIC
control module and the wiring.
With the warmed-up engine switched off and the ignition switch in the
Drive position, check that a 100 Hz PWM signal of 0.25-1.0 V is present
on pin 54.
Start the engine and check that the voltage applied to pin 54 is:
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•
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about 1.2 V at idling speed
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about 2.0 V at 2500 rpm
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about 12 V at full throttle.
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3.
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If the signal is absent or not OK, check the throttle position sensor, see
.
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4.
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If the throttle position sensor is OK and the signal from pin 54 is
absent or not OK, turn to
for further diagnostic
instructions.
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