Oxygen Sensor and Oxygen Sensor Control In Center Catalytic Converter, Checking

Oxygen Sensor And Oxygen Sensor Control In Center Catalytic Converter, Checking (vehicles With Engine Code BBW)

NOTE:
- Vehicle must be raised before connector for oxygen sensor is accessible.
- When servicing terminals 3 and 4 in harness connector of Heated Oxygen Sensor (HO2S), use only gold-plated terminals.

Recommended special tools and equipment
- V.A.G 1526 multimeter or V.A.G 1715 multimeter
- V.A.G 1594 connector test kit
- Wiring diagram

Requirements







- The respective fuses of Oxygen Sensor (O2S) in Center Three Way Catalytic Converter (TWC), Bank 1 -G465- must be OK.
- Battery voltage must be at least 11.5 Volts.
- All electrical consumers such as, lights and rear window defroster must be switched off.
- Parking brake must be engaged or else daylight driving lights will be switched on.
- For vehicles with automatic transmission, selector lever must be in position -P- or -N-.
- If vehicle is equipped with an A/C system, it must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Exhaust system must be properly sealed between catalytic converter and cylinder head.
- Coolant temperature must be at least 80 degrees C, Diagnostic mode 1: Check measured values; PID 5, Coolant temperature. Diagnostic Mode 1: Check Measured Values
- Oxygen sensor heater for oxygen sensor in center catalytic converter must be OK, check. Oxygen Sensor Heater For Oxygen Sensor In Center Catalytic Converter, Checking

Work sequence
- Select output of oxygen sensor signals and check whether specified values are being reached, Diagnostic mode 5: Check output of oxygen sensor signals. Diagnostic Mode 5: Check Output of Oxygen Sensor Signals
- End diagnosis and switch ignition off.

If specified values are not obtained:
- Check primary voltage.

Checking primary voltage







- Remove protective cover -1- and disconnect 4-pin harness connector (black) -4- to Oxygen Sensor (O2S) in Center Three Way Catalytic Converter (TWC), Bank 1 -G465- in center catalytic converter.







- Connect multimeter for voltage measurement to terminals 3 + 4 of connector to Engine Control Module (ECM) and measure primary voltage.

Specified value: 0.400 to 0.500 Volts

- Switch ignition off.

If specified value is not obtained:
- Check oxygen sensor wires.

If specified value is obtained:
- Replace Oxygen Sensor (O2S) in Center Three Way Catalytic Converter (TWC), Bank 1 -G465-.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 4: Reset/Erase Diagnostic Data
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

Checking oxygen sensor wires
- Connect test box to control module wiring harness, connect test box for wiring test. Test Box, Connecting For Wiring Test







- Check wires between test box and 4-pin connector (to control module) for open circuit according to wiring diagram.

Terminal 3 + socket 10
Terminal 4 + socket 11

Wire resistance: max. 1.5 Ohms

- Check wires for short circuit to B+ and to Ground (GND).

Specified value: Infinite Ohms

If no malfunctions are found in wires:
- Replace Motronic Engine Control Module (ECM) -J220-.