Mazda DTC P2196 Diagnostic

DTC P2196

 

 

Front HO2S signal stuck rich

 

DETECTION CONDITION

• The PCM monitors the front HO2S output voltage when the following conditions are met. If output voltage is more than 0.45 V for 41 s, the PCM determines that the front HO2S signal remains rich.

MONITORING CONDITION

– Fuel injection control system status: feedback zone

– ECT: more than 70 °C {158 °F}

– Engine speed: more than 1,500 rpm

Diagnostic support note

• This is a continuous monitor (HO2S).

• MIL illuminates if PCM detects the above malfunctioning condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.

• PENDING CODE is available if PCM detects the above malfunction conditions during first drive cycle.

• FREEZE FRAME DATA is available.

• DTC is stored in the PCM memory.
POSSIBLE CAUSE

• Front HO2S malfunction

• Fuel injector malfunction

• Excessive fuel pressure

• Restriction in intake-air system

• MAF sensor malfunction

• ECT sensor malfunction

• PCM malfunction

 

Diagnostic procedure

 
 

STEP

 

 

INSPECTION

 

 

ACTION

 

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED

• Has FREEZE FRAME DATA been recorded?

Yes

Go to the next step.

No

Record the FREEZE FRAME DATA on the repair order, then go to the next step.

2
VERIFY REPAIR INFORMATION AVAILABILITY

• Verify related service repair information availability.

• Is any related repair information available?

Yes

Perform repair or diagnosis according to the available repair information.

If the vehicle is not repaired, go to the next step.

No

Go to applicable DTC troubleshooting.

3
VERIFY RELATED PENDING CODE OR STORED DTC

• Turn the ignition switch off, then ON position (Engine off).

• Verify the related PENDING CODE or stored DTCs.

• Is the DTC P2177 or P2187 also present?

Yes

Go to the appropriate DTC inspection.

No

Go to the next step.

4
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA

• Is DTC P2196 on FREEZE FRAME DATA?

Yes

Go to the next step.

No

Go to FREEZE FRAME DATA DTC inspection.

5
VERIFY CURRENT INPUT SIGNAL STATUS

• Connect the WDS or equivalent to the DLC-2.

• Verify the following PIDs.

– ECT

– MAF

– TP

– VSS

• Are the PIDs normal?

Yes

Go to the next step.

No

Inspect the malfunctioning part according to the inspection results.

Then go to Step 10.

6
VERIFY CURRENT INPUT SIGNAL STATUS OF MAF SENSOR

• Connect the WDS or equivalent to the DLC-2.

• Start the engine.

• Access the MAF PID.

• Verify that the MAF PID changes quickly according to engine speed.

• Is the PID normal?

Yes

Go to the next step.

No

Replace MAF/IAT sensor, then go to Step 10.

7
INSPECT FRONT HO2S

• Inspect the front HO2S.

• Is there any malfunction?

Yes

Replace front HO2S, then go to Step 10.

No

Go to the next step.

8
INSPECT FUEL INJECTOR

• Inspect fuel injector.

• Is there any malfunction?

Yes

Replace suspected fuel injector, then go to Step 10.

 

No

Go to the next step.

9
INSPECT FUEL LINE PRESSURE

• Perform the “FUEL LINE PRESSURE INSPECTION”.• Is there any malfunction?

Yes

Replace the fuel pump unit, then go to the next step.

No

Go to the next step.

10
VERIFY TROUBLESHOOTING OF DTC P2196 COMPLETED

• Make sure to reconnect all disconnected connectors.

• Clear the DTC from the PCM memory using the WDS or equivalent.

• Perform the PCM Adopted Memory Produce Drive Mode and HO2S heater, and TWC Repair Verification Drive Mode.

• Is the PENDING CODE for this DTC present?

Yes

Replace PCM, then go to the next step.

No

Go to the next step.

11
VERIFY AFTER REPAIR PROCEDURE

• Perform the “After Repair Procedure”.

• Is there any DTC present?

Yes

Go to the applicable DTC inspection.

No

Troubleshooting completed.