With Manufacturer Scan Tool

Oxygen Sensor and Oxygen Sensor Control After Three Way Catalyst, Checking

Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551/1552 Scan Tool using VAG 1551/3 Adaptor cable
- VAG 1598/22 Test Box
- Fluke 83 multimeter
- VW 1594 Adaptor kit
- Wiring diagram

Requirements
- Engine Control Module MUST be matched to the Throttle Control Module.
- Exhaust system between Three Way Catalyst and cylinder head must be free of leaks
- Engine Coolant Temperature must be 85 °C minimum See Display group 04, Display field 3.

Functional check
- Connect VAG 1551/1552 Scan Tool. Refer to "Scan Tool Testing/Scan Tool Connecting and Initial Checks", Testing and Inspection
- Start engine and let idle
- Press 0 and 1 buttons to select "Engine Electronics" address word 01.

Indicated on display (example only)


06A906018AB Motronic M5.9.2 HS V06 ->
Coding 00000 WSC 00000


- Press -> button.

Indicated on display


Rapid data transfer HELP
Select function XX


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

Indicated on display


Read measuring value block
Input Display group number XXX


- Press 0, 3 and 6 buttons to select "Display group 36"
- Press Q button to enter input.

Indicated on display (1 to 4 = Display fields)


Read measuring value block 36 ->
1 2 3 4


- Check specifications for Oxygen control after Three Way Catalyst (Display fields 1 to 4).







If specifications obtained
- Press -> button.

Indicated on display


Rapid data transfer HELP
Select function XX


- Press 0 and 6 buttons to select "End output" function 06.
- Press Q button to enter input.
- Switch OFF ignition.
- Take test drive to remove possible residue build-up on Oxygen sensor and repeat check.

Observe appropriate safety precautions during road test.

If specification in Display field 1 is not obtained even after a test drive.
- Check Oxygen sensor heater after Three Way Catalyst. Oxygen Sensor, Checking
- Raise engine speed above 3000 RPM.

If value in Display field 1 remains constant, evaluating Display group 36.
- Press -> button.

Indicated on display


Rapid data transfer HELP
Select function XX


- Press 0 and 6 buttons to select "End output" function 06.
- Press Q button to enter input.
- Switch OFF ignition.

Display group 36, evaluating







Basic Voltage, checking







- Remove protective cover -arrows- and disconnect brown 4-pin harness connector to Oxygen sensor G39 (before Three Way Catalyst).
- Switch Fluke 83 multimeter to Voltage range







- Connect Fluke 83 multimeter between ECM harness connector terminals 3 + 4 using jumper wires from VW 1594 adaptor kit.
- Start engine and measure the basic Voltage.
- Specification: 0.40 to 0.50 Volts
- Switch OFF ignition.

If specification not obtained
- Check Oxygen sensor wiring.

If specification obtained
- Replace Oxygen sensor 2 G130.
- Display the Readiness code. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Displaying Readiness Code", Monitors, Trips, Drive Cycles and Readiness Codes
- If DTC memory was erased or if the ECM was disconnected from Battery + , set the Readiness code. Refer to "Monitors, Trips and/or Drive Cycle (Readiness Codes)/Setting Readiness Code", Monitors, Trips, Drive Cycles and Readiness Codes

Oxygen sensor 2 wiring, checking







- Connect VAG 1598/22 Test Box to ECM wiring harness.







- Check wiring for open circuit between Test Box and 4-pin harness connector to ECM using Wiring diagram.
- Terminal 3 + socket 51
- Terminal 4 + socket 52
Wire resistance: maximum: 1.5 Ohms

- Also check wiring at 4-pin harness connector for shorting to one another.

Terminal 4 + socket 51 specification: Infinity Ohms
- Check shield for short to sensor wiring using wiring diagram.
- Terminal 4 + socket 14
- Terminal 3 + socket 14
Specification: Infinity Ohms

If wiring OK:
- Replace Engine Control Module.