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Camshaft Position Sensor

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 .

The Camshaft Position (CMP) sensor is located on the rear of the cylinder head. Location of CMP harness connection. See COMPONENT LOCATIONS .

  1. Connect (VAG 1598) test box to Engine Control Module (ECM) using (VAG 1598/5) adaptor cable. See CONNECTING VAG 1598 TEST BOX .
  2. Connect LED Tester (US 1115) between terminals No. 8 and 12. Operate starter for a few seconds. LED tester must blink briefly during every second engine revolution. If LED tester does not blink, switch ignition OFF.
  3. Disconnect 3-pin CMP sensor connector at distributor. See Fig 1.
  4. Using DVOM, switched to resistance range. Check wires according to the wiring diagram for continuity and/or short circuit to each other, as described below. See Figure and Fig 1 . See WIRING DIAGRAMS .
  5. Check wires:
    • Between CMP sensor connector terminal No. 1 and test box socket 19.
    • Between CMP sensor connector terminal No. 2 and test box socket 8.
    • Between CMP sensor connector terminal No. 3 and test box socket 12.
    If necessary, repair open circuit and/or short circuit in wiring between CMP sensor harness connector and ECM harness connector terminal No. 8, 12 and 19. See Figure. See WIRING DIAGRAMS .
  6. If there is neither an open circuit nor a short circuit, using DVOM, switched to 20 Volt range.
  7. Connect DVOM to terminals No. 12 and 19 using adapter cables from (VW 1594) adaptor kit.
  8. Switch ignition ON. Voltage must be 4.5-5.5 volts. Switch ignition to OFF position.
  9. Connect DVOM to terminals No. 8 and 19.
  10. Switch ignition ON. Voltage must be 4.3-5.2 volts. Switch ignition OFF.
  11. If NO in each case: Replace ECM. After replacement of ECM, see ECM IDENTIFICATION and ECM CODING under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS article.
  12. If YES in each case: Replace Camshaft Position (CMP) sensor and set basic adjustment. See CAMSHAFT POSITION SENSOR BASIC ADJUSTMENT  under IGNITION SYSTEMS.
Fig 1: Identifying Camshaft Position Sensor Wiring Harness Connector
G00149775Courtesy of AUDI OF AMERICA, INC.