V8 Quattro V8-3562cc 3.6L DOHC (PT) (1990)
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V-8 MOTRONIC Start-Up Reference Signals
The ECM uses this information during engine cranking only, and compared with the signal from the hall sensor in the distributor, provides a reference
point from which to calculate the ignition timing and synchronize the fuel injection pulses so the engine will start. Once the engine is started, the signal
from the reference sensor is no longer needed, and the ECM calculates the ignition timing and fuel injection pulses using the signal from the engine
speed sensor.
SELF DIAGNOSIS
The ECM will recognize when the signal is absent, and store a fault code, indicating that the pin is missing, or there is an open or short circuit in the
sensor or sensor wiring. There is no substitute signal for this sensor. If the reference sensor fails or the signal is lost (due to open or shorted wire, or
missing reference pin) while the engine is running, the engine will continue to run until the ignition is turned off, but will not start again until the sensor
is replaced or the sensor signal is restored (wire is repaired or reference pin is replaced).
Diagnostic Trouble Code # 00514 is displayed on the VAG 1551 scan tool for the absence of a signal.
Blink Code # 2112 is displayed using blink code extraction for the absence of a signal.
