SAAB WIS ONLINE

DTC P0131 or P0132

DTC P0131 or P0132

Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• Diagnostic Procedure Instructions provides an overview of each diagnostic category.


DTC Descriptors

DTC P0131 01

HO2S Circuit Low Voltage Sensor 1

DTC P0131 12

HO2S Circuit Low Voltage Sensor 1

DTC P0131 52

HO2S Circuit Low Voltage Sensor 1

DTC P0131 5A

HO2S Circuit Low Voltage Sensor 1

DTC P0132 02

HO2S Circuit High Voltage Sensor 1

DTC P0132 11

HO2S Circuit High Voltage Sensor 1

DTC P0132 52

HO2S Circuit High Voltage Sensor 1

DTC P0132 5B

HO2S Circuit High Voltage Sensor 1

Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performance
Heater Voltage Supply

P0030 00

P0030 00

-

P0131 5A, P0131 12

Reference Voltage (Signal)

P0131 01

P0131 12, P2243 00, P2231 00

P0131 02, P2231 00

P0133 00, P0131 52, P0131 5A, P0132 52, P0132 5B

Signal (Pump Current)

P2626 00

P2626 00

P2626 00, P2231 00

-

Signal (Trim Current)

P2626 00

P2626 00

P2626 00

-

Heater Low Control

P0031 00

P0030 00

P0032 00

-

Low Reference (Ground)

P2A00 00

P0132 02, P2243 04

P0132 02

-



Typical Scan Tool Data

HO2S Bank 1 Sensor 1

HO2S Sensor Voltage Circuits Normal Range Short to Ground Open Short to Voltage
HO2S High Signal

0-1 000 mV

0-90 mV

350-550 mV

Approximately 1 100 mV

HO2S Low Signal

0-1 000 mV

0-1 000 mV

0-1 000 mV

0-1 100 mV



Circuit/System Description

The heated broadband oxygen sensor (HO2S) measures the quantity of oxygen in the exhaust stream faster and more accurately than an HO2S of a switching type. The broadband probe consists of a oxygen detection cell, an oxygen pumping cell and a heater. The exhaust gas sample passes through a diffusion gap between the sensing cell and the pumping cell. The engine control module (ECM) supplies a signal voltage to the HO2S and uses this voltage as a reference to the amount of oxygen in the exhaust system. An electronic circuit within the ECM controls the pump current through the oxygen pumping cell in order to maintain a constant signal voltage. The ECM monitors the voltage variation on the signal circuit and attempts to keep the voltage constant by increasing or decreasing the amount of current flow or reversing the direction of the current flow to the pumping cell. By measuring the direction and amount of current required to maintain the signal voltage, the ECM can determine the concentration of oxygen in the exhaust. The signal voltage is displayed as a lambda value. A lambda value of 1 is equal to a stoichiometric air fuel ratio of 60:1. Under normal operating conditions, the lambda value will remain around 1. When the system is lean, the oxygen level will be high and the lambda value will be high, or more than 1. When the system is rich, the oxygen level is low and the lambda value will be low, or less than 1. The ECM uses this information to maintain the proper air/fuel ratio.

Conditions for Running the DTC


P0131 and P0132

• The system voltage is between 10-18 V.

• The scan tool special functions are not active

• The Throttle Position Indicated Angle parameter is between 3-90%.

• The Loop Status parameter is closed.

• The traction control is not active.

• The above conditions must be met for at least 5 seconds.


Conditions for Setting the DTC


P0131

• The ECM detects that the HO2S 1 signal voltage is less than 50 mV for more than 2 seconds.

• This diagnostic runs continuously.



P0132

• The ECM detects that the HO2S 1 signal voltage is more than 1 050 mV for more than 2 seconds.

• This diagnostic runs continuously.


Action Taken When the DTC Sets

DTCs P0131 and P0132 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0131 and P0132 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference


• Circuit Testing

• Connector Repairs

• Heated Oxygen Sensor Wiring Repairs

• Testing for Intermittent Conditions and Poor Connections

• Wiring Repairs


DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification


1. Clear the DTCs with a scan tool.

2. Operate the vehicle within the conditions to run and set the DTC. The DTC should not be set.

3. Run the vehicle within the Conditions for Running the DTCs. You may also operate the vehicle within the conditions that you have noted from the Freeze Frame/Failure Records data.


Circuit/System Testing

Note

All modules must be powered down or misdiagnosis may result.



1. Ignition OFF, disconnect the scan tool and wait 60 seconds to ensure all modules are powered down.

2. Disconnect the harness connector at the B52A Heated Oxygen Sensor 1.

3. Test for less than 5 Ω between the low reference circuit terminal 2 X1 and ground.

4. If more than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

5. Ignition ON, verify the scan tool HO2S Bank 1 Sensor 1 parameter is approximately 450 mV.

6. If more than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

7. If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

8. Ignition ON, install a 3 A fused jumper wire at the HO2S high signal circuit terminal B. Toggle the jumper wire between the HO2S low signal circuit terminal A and the battery voltage. Verify the appropriate scan tool HO2S parameter toggles between 0 mV and approximately 1 000 mV.

9. If the appropriate scan tool HO2S parameter does not toggle correctly, test the HO2S high signal circuit for an open/high resistance. If the circuits test normal, replace the K20 Engine Control Module.

10. If all circuits test normal, replace the appropriate HO2S Sensor.


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


• Heated Oxygen Sensor Replacement - Sensor 1

• Control Module References