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CIS-E III (Engine Code MC With 1 Knock Sensor)

  1. Locate 2 diagnostic connectors in drivers footwell area. Connect a test light between connectors A and B. See Fig 1 .
  2. Connect a jumper wire to other terminal in connector A. Touch other end of jumper wire to remaining terminal in connector B for at least 4 seconds. Fault codes will now be displayed by the flashing CHECK light (California vehicles) or test light (Federal vehicles).
    NOTE: Pay careful attention to flashing light since there are no discernible break points between 4-digit fault codes.
  3. Trouble codes will be flashed as 4-digit numbers. There is a 1/2-second pause between flashes. Add flashes together to obtain code for each of the four digits. See Figure . There is a 2 1/2-second pause before code for next digit is flashed. After code for the fourth (last) digit is flashed, there's another 2 1/2-second pause before fault code is repeated.
    Fig 1: Identifying Diagnostic Connectors (For Engines With 1 Knock Sensor)
    G121424Courtesy of AUDI OF AMERICA, INC.
  4. Fault code will be repeated until the ignition is turned off. Record fault code. Check the list of input codes and possible problems. See CIS-E III SINGLE KNOCK SENSOR ENGINE CODE MC CONTROL INPUT FAULT CODES table.
  5. Check and repair circuits and/or sensors as indicated. See appropriate test in SYSTEM & COMPONENT TESTING article. After the fault is corrected, check for additional codes.
  6. To display next fault code, repeat step 2). (Touch remaining end of jumper wire to remaining terminal in connector B for at least 4 seconds.) See Fig 1 . Continue checking for fault codes until Code 0000 is displayed, indicating end of diagnosis. Code 0000 is indicated by light remaining off for approximately 15 seconds after start signal.
CIS-E III SINGLE KNOCK SENSOR ENGINE CODE MC CONTROL INPUT FAULT CODES

Code System Affected Probable Cause
1111 Control Unit Defective Memory Circuits
2111 Engine Speed Sensor Control Unit Not Receiving Signal
2112 Reference Sensor (1) Control Unit Not Receiving Signal
2113 Hall Sender In Distributor (2) Control Unit Not Receiving Signal
2221 Control Unit Pressure Sensor Vacuum Hose Leaks/Plugged
2221 Control Unit Pressure Sensor Defective Pressure Sensor
2141 Knock Regulation (3) Engine or Ignition Knock
2142 Knock Sensor Defective Sensor or Sensor Wiring
2123 Full Throttle Switch Faulty Switch or Wiring Problem
2121 Idle Switch Faulty Switch or Wiring Problem
2312 Coolant Temp. Sensor Sensor or Wiring Defective
2322 Intake Air Temp. Sensor Sensor or Wiring Defective
2342 Oxygen Sensor Sensor or Sensor Wiring Defective
4444 No Faults Have Been Recorded N/A
0000 End of Diagnosis (4)
(1) Another cause could be a misadjusted distributor.
(2) Another cause could be signal is out of phase (misadjusted distributor).
(3) This would cause ignition timing to be retarded the maximum amount (7.8 degrees).
(4) This code is indicated by the light staying off for approximately 15 seconds after the start signal.
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