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Home >> Audi >> 2001 >> A4 Base, 2.8 H, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.8L >> Diagnostic Tests >> DTC P1111/17519: Oxygen Sensor Control Bank 1 System To Lean Or DTC P1112/17520: Oxygen Sensor Control Bank 1 System To Rich
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DTC P1111/17519: Oxygen Sensor Control Bank 1 System To Lean Or DTC P1112/17520: Oxygen Sensor Control Bank 1 System To Rich

NOTE: VAS 5051 scan tool with VAG 5051/1 adapter cable or VAG 1551 scan tool with VAG 1551/3B adapter cable and VAG 1598/31 test box are necessary to diagnose this code. Follow test equipment manufacturer's instructions for scan tool operation.
NOTE: When Engine Control Module (ECM) switches oxygen sensor heating on and off, it may be observed in scan tool function "08 - READ MEASURING VALUE BLOCK", in display field 4 of display groups 041 and 042.
NOTE: For aid in troubleshooting this procedure, diagnostic function 04 - BASIC SETTING FUNCTION allows oxygen sensor control to be switched off. Oxygen sensor control is switched on again in diagnostic function 08 - READ MEASURING VALUE BLOCK. Once oxygen sensor control is switched on and off as described, pressing buttons 4 or 8 allows for switching between diagnostic functions BASIC SETTING FUNCTION AND READ MEASURING VALUE BLOCK. When diagnostic functions are exited oxygen sensor control is automatically switched on.
  1. Ensure that exhaust system is free of leaks. Start engine and road test vehicle until engine coolant temperature is at least 176 °F (80 °C). Connect VAS 5051 or equivalent scan tool to DLC. DLC is located behind cover under left side of steering column. Start engine, and increase engine speed to 2600 RPM. Using scan tool, select "01 - ENGINE ELECTRONICS". From selection, 1 select diagnostic function "04 - BASIC SETTING" function. Press "Q" button to confirm input. Leave engine running, and go to next step.
  2. From button field 2, enter 030 for "DISPLAY GROUP NUMBER 030". Press "Q" button to confirm input. Observe oxygen sensor status in display fields 1 and 2. See Figure. If displayed value is as specified, and DTC is stored in memory, go to next step. If displayed value is not as specified, go to step  9.
  3. On scan tool press "C" button. From button field 2, enter 033 for "DISPLAY GROUP NUMBER 033". Observe oxygen sensor control values in display fields 1 and 3. See Figure. If displayed values are not as specified, go to next step. If displayed values are as specified, go to step  16.
  4. If specified value in display fields 1 and 3 is not obtained, or if displayed value does not fluctuate at least 2%. Test drive car to condition oxygen sensor and repeat test. If after test drive, specified values in display fields 1 and 3 are still not as specified, go to next step. If after test drive, specified values in display fields 1 and 3 are as specified, go to step  6.
  5. If displayed values range between -10 to - 25 %, 10 to 25 % or value does not fluctuate by 2 % or more, check for following conditions:
    • Oxygen sensor heating faulty. Check oxygen sensor heating. For diagnostic procedure, go to DTC P1115/17523, P1116/17524, P1117/17525, P1118/17526, P1119/17527, P1120/17528, P1121/17529 OR P1122/17530 .
    • Open circuit in wires between oxygen sensor and ECM. Check circuits, go to step  9.
    • Short to ground or voltage between oxygen sensor and ECM. Check circuits, go to step  9.
    • Check air intake system for leaks (false air).
    • Fuel pressure too high or low. Check fuel pressure, see FUEL SYSTEM in SYSTEM & COMPONENT TESTING article.
    • Fuel return line is clogged or kinked. Check fuel lines between fuel injectors and fuel tank.
    If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
  6. On scan tool press "C" button. From button field 2, enter 032 for "DISPLAY GROUP NUMBER 032". Observe oxygen sensor adaptation values in display fields 1-3. See Fig 1. If displayed values range between -10 to -25 %, go to next step. If displayed values range between 10 to 25 %, go to step  8. If displayed values are as specified, go to step  16.
  7. If displayed values range between -10 to -25 %, check for following conditions:
    • Oil thinning (fuel in oil). Change oil and filter as necessary.
    • High oil consumption.
    • MAF sensor faulty. Check MAF sensor. For diagnostic procedure, go to DTC P0101/16485, P0102/16486 OR P0103/16487 .
    • Evaporative Emissions (EVAP) canister purge regulator valve stuck open. Check EVAP valve. For diagnostic procedure, go to DTC P1410/17818 .
    • Fuel pressure too high. Check fuel pressure, see FUEL SYSTEM in SYSTEM & COMPONENT TESTING article.
    • Fuel return line is clogged or kinked. Check fuel lines between fuel injectors and fuel tank.
    • Fuel injector does not close. Check fuel injectors, see FUEL SYSTEM in SYSTEM & COMPONENT TESTING article.
  8. If displayed values range between 10 to 25 %, check for following conditions: If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
    9. NOTE: Oxygen sensor harness connectors are more easily accessed by temporarily moving coolant reservoir. Leave coolant hoses connected.
  9. Turn ignition off. Disconnect all oxygen sensor 4-pin harness connectors. See Figure or Figure . Inspect oxygen sensor harness connectors for looseness and/or corrosion. If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
  10. Using DVOM, measure voltage between suspect oxygen sensor harness connector terminals No. 3 and 4 (female terminal side). See Figure. Voltage should be.4-.5 volt. If voltage is not as specified for bank one oxygen sensors, go to next step. If voltage is as specified, go to step  16.
  11. Turn ignition off. Disconnect suspect bank one oxygen sensor 4-pin harness connector. Disconnect ECM harness connectors. ECM is located in left rear corner of engine compartment, in electronics box. Connect VAG 1598/31 test box to ECM wiring harness (leave ECM disconnected). Check for open in specified circuits between oxygen sensor harness connector (female terminal side) and specified VAG test box sockets. See CHECKING OXYGEN SENSOR CIRCUITS (BANK 1)  table. See Figure. If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
    CHECKING OXYGEN SENSOR CIRCUITS (BANK 1)

    Heated Oxygen Sensor Terminal VAG Test Box Socket
    3 51
    4 70
  12. Check wires for short to each other. Check circuits between oxygen sensor harness connector terminal No. 4 and VAG test box socket No. 51. If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
  13. Check shielded wires for short to oxygen sensor wires. Check between oxygen sensor harness connector terminals No. 3 and 4 and VAG test box socket No. 32. If no problem is found, go to next step. If problem is found, repair as necessary. After repair, go to step  16.
  14. Replace ECM. See ENGINE CONTROL MODULE REPLACEMENT . After repair, go to step  16.
  15. Replace suspect oxygen sensor. See REMOVAL, INSTALLATION & OVERHAUL article. After repair, go to next step.
  16. Using scan tool, clear DTCs and generate a ECM readiness code. See FUNCTION 05 - CLEARING DIAGNOSTIC TROUBLE CODES  and READINESS CODE  under SELF-DIAGNOSTIC SYSTEM. Test drive vehicle. Using scan tool, retrieve DTCs. If DTC does not reset testing is complete.
Fig 1: Display Group 032: Oxygen Sensor Adaptation Values
G00077153Courtesy of AUDI OF AMERICA, INC.
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