Mode 5: Check Oxygen Sensor Output Signals
Mode 5: Check Oxygen Sensor Output Signals
The static values of the oxygen sensors are indicated in this diagnostic mode.
The values of the individual oxygen sensor signal outputs must reach the specified value or must be within the min.- and max.- limits.
Test requirements:
- No DTCs in DTC memory; Check DTC memory. Mode 3: Check DTC Memory
- Coolant temperature at least 80 degree C see "Mode 1: Check measuring values "; "PID 05: Coolant temperature", Mode 1: Check Measured Values
Procedure
- Connect diagnostic tester. Connect Diagnostic Tester
- Start engine and let run at idle.
- In diagnostic function "33 - OBD", select "Mode 5: Check output of oxygen sensor signals".
- Via the following table, select the desired output of oxygen sensor signals according to Test ID (Test Identification), e.g. "01: Rich to lean sensor barrier voltage".
- Check specified values at idle.
NOTE:
- When selecting the diagnostic mode, the entry is always performed in "Bank 1 sensor 1".
- If either the V.A.G 1551/1552 Scan Tool (ST) or the VAS5051/5052 Vehicle Diagnostic, Testing and Information System is used for checking the output of oxygen sensor signals, the respective oxygen sensor can be selected by pressing buttons 1 and 2:
- Button 1 = Bank 1 sensor 1,
- Button 2 = Bank 1 sensor 2.
Test-ID1) Diagnostic text
01: Rich to lean sensor barrier voltage
02: Lean to rich sensor barrier voltage
07: Minimum voltage at sensor for test cycle
08: Maximum voltage at sensor for test cycle
129: Current value of oxygen sensor signal
130: Specified value of oxygen sensor signal
131: Dynamic value
132: Shift of oxygen sensor regulation before catalytic converter via oxygen sensor regulation behind catalytic converter
1) Test IDs that are not relevant are not listed.
- End diagnosis and switch ignition off.
Evaluation test-ID 01: Rich to lean sensor barrier voltage
Oxygen sensor Specified value
Bank 1, sensor 2 0.575 V
If specified value is not obtained:
- Replace oxygen sensor behind catalytic converter.
Evaluation test-ID 02: Lean to rich sensor barrier voltage
Oxygen sensor Specified value
Bank 1, sensor 2 0.575 V
If specified value is not obtained:
- Replace oxygen sensor behind catalytic converter.
Evaluation test-ID 07: Minimum voltage at sensor for test cycle
If the specified value is not reached:
- Short circuit to Ground (GND) in oxygen sensor or in wire.
- Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC).
If the specified value is exceeded:
- Oxygen sensor not ready for operation
- Oxygen sensor heater faulty
- Test oxygen sensor heater behind catalytic converter.
- Short circuit to B+ or open circuit in wiring in oxygen sensor or in wire.
- Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC).
Evaluation test-ID 08: Maximum voltage at sensor for test cycle
If the specification is exceeded or not met:
- Oxygen sensor not ready for operation
- Oxygen sensor heater faulty
- Test oxygen sensor heater behind catalytic converter.
- Short circuit to Ground (GND) or B+ or open circuit in wiring in oxygen sensor or in wire.
- Check Oxygen Sensor (O2S) and oxygen sensor control behind Three Way Catalytic Converter (TWC).
Evaluation test-ID 129: Current value of oxygen sensor signal
1) Control module internal calculated value
If the specification is exceeded or not met:
- Oxygen sensor not ready for operation
- Oxygen sensor heater faulty
- Test oxygen sensor heater before catalytic converter.
- Short circuit to Ground (GND) or B+ or open circuit in wiring in oxygen sensor or in wire.
- Oxygen sensor faulty
- Check Oxygen Sensor (O2S) and oxygen sensor control before Three Way Catalytic Converter (TWC).
Evaluation test-ID 130: Specified value of oxygen sensor signal
1) Control module internal calculated value
If the specification is exceeded or not met:
- Replace Engine Control Module (ECM).
Evaluation test-ID 131: Dynamic value
1) Control module internal calculated value
If the specified value is not reached:
- Oxygen sensor is aged
- Replace oxygen sensor before catalytic converter.
Evaluation test-ID 132: Shift of oxygen sensor regulation before catalytic converter via oxygen sensor regulation behind catalytic converter
1) Control module internal calculated value
If the specified value is not reached:
- Oxygen sensor not ready for operation
- Oxygen sensor heater faulty
- Test oxygen sensor heater before catalytic converter.
- Short circuit to Ground (GND) or open circuit in wiring in oxygen sensor or in wire.
- Oxygen sensor faulty
- Check Oxygen Sensor (O2S) and oxygen sensor control before Three Way Catalytic Converter (TWC).
- Mixture too rich
- Check fuel pressure regulator and residual pressure.
- Check fuel injectors. Fuel Injectors, Checking
- Check Evaporative Emission (EVAP) canister purge regulator valve -N80-. With Manufacturer's Scan Tool
If the specified value is exceeded:
- Oxygen sensor not ready for operation
- Oxygen sensor heater faulty
- Test oxygen sensor heater before catalytic converter.
- Short circuit to B+ or open circuit in wiring in oxygen sensor or in wire.
- Oxygen sensor faulty
- Check Oxygen Sensor (O2S) and oxygen sensor control before Three Way Catalytic Converter (TWC).
- Mixture too lean
- Checking system pressure and residual pressure. Testing and Inspection
- Check fuel injectors. Fuel Injectors, Checking
- Check intake system for leaks (false air). [1][2]Testing and Inspection
- Check Fuel Pump (FP). Testing and Inspection
- Check exhaust system for proper seal.
- Check Secondary Air Injection (AIR) system for proper seal. Secondary Air Injection (AIR) System, Checking For Proper Seal
- Check vacuum lines for proper seal.
Final procedures
After repair work, the following work steps must be performed in the mentioned sequence:
1. Check DTC memory. Mode 3: Check DTC Memory
2. If necessary, erase DTC memory. Mode 4: Reset/Erase Diagnostic Data
3. Generate readiness code. Readiness Code, Generating
- End diagnosis and switch ignition off.