V8 Quattro V8-3562cc 3.6L DOHC (PT) (1990)
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Knock Sensor
The knock sensor contains a piezo-ceramic crystal element. When mechanical forces act upon a crystal, causing distortion of the crystal, small
electrical charges are generated on the crystals surface. When a knock occurs in the engine, the frequency and magnitude of the sound wave that is
generated causes small distortions in the knock sensor crystal, generating a voltage on the surface of the crystal which the ECM reads.
SELF DIAGNOSIS
The ECM will recognize the absence of a signal, indicating an open or shorted sensor or sensor circuit. There is no substitute signal for this input.
Diagnostic Trouble Code # 00524 is displayed on the VAG 1551 scan tool for Knock sensor I.
Blink Code # 2142 is displayed using blink code extraction for Knock sensor I.
Diagnostic Trouble Code # 00540 is displayed on the VAG 1551 scan tool for Knock sensor II.
Blink Code # 2144 is displayed using blink code extraction for Knock sensor II.
