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With Manufacturer's Scan Tool




Oxygen Sensor (O2S) and Oxygen Sensor (O2S) control behind TWC, checking

NOTE:
- Connector for Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC) -G130- (bank 1, sensor 2): 4-pin, green.
- Connector for Oxygen Sensor (O2S) 2 behind Three Way Catalytic Converter (TWC) -G131- (bank 2, sensor 2): 4-pin, brown.

Required special tools and test equipment
- VAG 1551 or VAG 1552 Scan Tool (ST) with VAG 1551/3 adapter cable
- VAG 1598/22 test box
- Multimeter US 1119 (Fluke 83 or equivalent)
- VW 1594 connector test kit
- Wiring diagram

Test requirements
- Engine Coolant Temperature (ECT) at least 80 ° (176 ° F)

Function test
- Connect VAG 1551 or VAG 1552 scan tool and press buttons -0- and -1- to insert "Engine Electronics" address word 01 (with engine running at idle).Refer to "Scan tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG 1551/VAG 1552 Scan Tool" [1][2]Scan Tool Connecting and Initial Checks

Indicated on display


Rapid data transfer HELP
Select function XX


- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08, and press -Q- button to confirm input.

Indicated on display


Read Measuring Value Block HELP
Input display group number XXX


- Press buttons -0-, -3- and -6- to input display group number 36 (036), and press -Q- button to confirm input.

Indicated on display (1-4 = display fields)

Read Measuring Value Block 36 ->
1 2 3 4

- Compare display and specified values (display fields 1-4):


Display Group 36:






Continuation
- Road test to condition oxygen sensor (eliminate possible contamination) and repeat test.

If the values are still NOT OK:

- Check Oxygen Sensor (O2S) heater(s).
- Briefly accelerate engine over 3000 RPM.

If the value in either display field 1 or field 3 remains constant, Evaluation of display group 36.

Evaluation of display group 36, display fields 1,3


Display Group 36:






Checking O2S reference voltage

- Disconnect 4-pin connector for respective Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC).







- Connect multimeter US 1119 (Fluke 83 or equivalent) between harness connector terminals 3 and 4 (to ECM), using adapter cables from VW 1594 connector test kit.

- Start engine and measure voltage.
Specified value: 0.40 to 0.50 volts
- Switch ignition off.

If voltage is NOT OK:
- Check O2S wiring.
- Bank 1, sensor 2.
- Bank 2, sensor 2.

If voltage is OK:
- Replace respective O2S behind TWC.

Checking O2S wiring, bank 1, sensor 2

- Disconnect 4-pin connector (green) for Oxygen Sensor (O2S) behind Three Way Catalytic Converter (TWC) -G130-.
- Connect VAG 1598/22 test box to ECM harness connector.Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG 1598/22 Test Box" [1][2]Scan Tool Connecting and Initial Checks







- Check wiring for open circuit between ECM/test box and 4-pin O2S harness connector (to ECM).
- Connector terminal 3 to ECM/test box socket 51
- Connector terminal 4 to ECM/test box socket 52
- Specified value: max. 1.5 Ohms

- Check wiring for short circuits between terminals of 4-pin connector.
- Connector terminal 4 to ECM/test box socket 51
- Specified value: Infinity Ohms

- Check shielding wire for short circuit to sensor wires.
- Connector terminal 4 to ECM/test box socket 14
- Connector terminal 3 to ECM/test box socket 14
- Specified value: Infinity Ohms

If wiring is OK:
- Replace Motronic ECM -J220-.
- Carry out adaptation of throttle valve control module to ECM.
- Check readiness code. If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code. Audi Drive Cycle/Readiness Code

Checking O2S wiring, bank 2, sensor 2

- Disconnect 4-pin connector (brown) for Oxygen Sensor (O2S) 2 behind Three Way Catalytic Converter (TWC) -G131-.
- Connect VAG 1598/22 test box to ECM harness connector.Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks/Connecting VAG 1598/22 Test Box" [1][2]Scan Tool Connecting and Initial Checks







- Check wiring for open circuit between ECM/test box and 4-pin O2S harness connector (to ECM).
- Connector terminal 3 to ECM/test box socket 38
- Connector terminal 4 to ECM/test box socket 50
- Specified value: max. 1.5 Ohms

- Check wiring for short circuits between terminals of 4-pin connector.
- Connector terminal 4 to ECM/test box socket 38
- Specified value: Infinity Ohms

- Check shielding wire for short circuit to sensor wires.
- Connector terminal 4 to ECM/test box socket 14
- Connector terminal 3 to ECM/test box socket 14
- Specified value: Infinity Ohms

If wiring is OK:
- Replace Motronic ECM -J220-.
- Carry out adaptation of throttle valve control module to ECM.
- Check readiness code.If Diagnostic Trouble Code (DTC) memory has been erased, or ECM was disconnected, generate new readiness code. Audi Drive Cycle/Readiness Code
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