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Trouble Codes

  1. Drive vehicle for a minimum of 5 minutes to allow fault information to be stored. If a no-start condition exists, operate starter for at least 6 seconds.
    CAUTION: DO NOT turn ignition off. This will erase the fault memory.
    Fig 1: Location of Fuel Pump Relay
    G61291Courtesy of AUDI OF AMERICA, INC.
  2. Insert fuse into fuel pump relay for at least 4 seconds. See Fig 1 . Indicator light on instrument cluster should display a 4 digit fault code from ICU.
  3. If indicator light displays a Code 4444, no faults have been recorded. Record all fault codes by repeating step 2) until a Code 0000 is displayed. This indicates that all fault codes from ICU have been displayed.
  4. Repeat step 2) after Code 0000 is displayed. This time, however, faults that are displayed will be from FICU. Engine speed may increase. Record all codes.
  5. Repeat step 2) until all FICU fault codes have been displayed. When all fault codes from FICU have been displayed, a Code 0000 will display.
  6. For a list of all ICU and FICU fault codes, refer to SELF-DIAGNOSTIC FAULT CODES  table.
SELF-DIAGNOSTIC FAULT CODES

Code Location of Fault Problem
1111 ICU or FICU Defective Memory Circuits In Control Unit
2121 Idle Switch Switch Stuck Closed or Problem in Wiring to Switch
2122 Engine Speed Signal or Hall Sender No Engine Speed Signal from ICU Term. No. 17
2123 Full Throttle Switch Switch Stuck Closed or Problem in Wiring to Switch
2132 (1) No Data Transmitted from FICU to ICU Disconnected or Open Wire between ICU Term. No. 5 & FICU Term. No. 1 or ICU Term. No. 3 & FICU Term. No. 13 or Defective Control Units
2141 Knock Regulation Engine or Ignition Knock is Causing Timing to be Retarded (Max. Limit)
2142 Knock Sensor Defective Sensor or Sensor Wiring
2223 Altitude Sensor No Signal from Sensor
2232 Air Sensor No Signal from Sensor to FICU or Break in Wire between FICU Term. No. 21 & ICU Term. No. 8
2233 Reference Voltage for Air Sensor & Altitude Sensor No Reference Voltage from ICU Term. No. 21 & FICU Term. No. 26
2312 Cool. Temp. Sensor No Signal from Sensor
2341 O2 Sensor Control O2 Sensor Control Operating at Rich or Lean Limit
2342 02 Sensor No Signal from Sensor
4431 Idle Stab. Valve Problem in Wiring to Idle Stab. Valve
4444 No Faults Stored N/A
0000 End of Diagnosis N/A
(1) Calif. only.