Notes

Knock Sensor: Notes — 1994 Audi S4 Service Manual & Component Testing >> Engine Sensors & Switches >> Knock Sensor >> Notes Knock Sensor: Notes NOTE: All voltage and continuity tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated differently in testing procedures. For help with diagnostic testing. See WIRING DIAGRAMS. Location of Knock (KS1 and KS2) sensors and harness connections. See COMPONENT LOCATIONS. The knock sensors cannot be checked electrically. Check DTC memory. See RETRIEVING DIAGNOSTIC TROUBLE CODES in SELF-DIAGNOSTICS article. For satisfactory function of the knock sensors, exact compliance with the tightening torque of 15 ft. lbs (20 N.m) is important. Check the harness connection from knock sensor to wiring harness for corrosion. Connect (VAG 1598) test box to Engine Control Module (ECM) wiring harness using (VAG 1598/5) adaptor cable. See CONNECTING VAG 1598 TEST BOX. Disconnect knock sensors at harness connections. Check wires for continuity and/or short circuits to each other. Using DVOM switched to resistance range, check for the following conditions: Short circuit (1.0 ohm maximum). Open circuit approximately (1 milliohm to infinite ohms). For connector view, see Figure and Figure.