DTC P2273 [AJ (3.0L Duratec)]


id0102a4827500

DTC P2273

Lack of HO2S-22 switch, sensor indicates rich

DETECTION CONDITION

• The PCM monitors HO2S-22 signal switching during forced lean at PCM terminal 61. If the PCM does not detect signal input from HO2S-22 for calibrated amount of time, the PCM determines that HO2S-22 cannot switch to lean.

POSSIBLE CAUSE

• Pinched, shorted, and corroded wiring and pins
• Crossed sensor wires
• Exhaust leaks
• Contaminated or damaged HO2S-22

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 the next step.
3
INDETIFY TRIGGER DTC FOR FEEZE FRAME DATA
• Is DTC P2273 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to FREEZE FRAME DATA DTC inspection.
4
VISUALLY INSPECT FOR HO2S-22
Note
• Address all Continuous Memory Ignition and Misfire DTCs, before any KOER HO2S-22
• Visually inspect for HO2S-22 followings:
- Pinched, shorted and corroded wiring and pins
- Crossed sensor wires
- Contaminated or damaged sensor
• Were any concerns found during inspection?
Yes
Repair or replace for malfunctioning part, then go to Step 12.
No
Go to the next step.
5
CHECK FOR KOER DTCS
• Start the engine.
• Run the engine at approx. 2,000 rpm and maintain engine speed for 3 minutes.
• Perform KOER self-test.
• Are DTCs P1137, P2270, P1157, P2272, P1138, P2271, P1158, P2273, P2274 or P2275 present?
Yes
Go to the next step.
No
Intermittent concern exist, then go to the next step.
6
CHECK HO2S SIGNAL LEVEL TOO HIGH
Note
• Fuel calculations can be affected by abnormal air leaks.
• Carefully inspect the following areas for potential air leaks:
- Hoses connecting to MAF sensor assembly.
- Hoses connecting to throttle body.
- Intake manifold gasket leaks.
- PCV disconnected.
- The vacuum lines are disconnected.
- Improperly seated engine oil dipstick, tube or oil fill cap.
- Exhaust gas leaks at flanges and gaskets.
• Raise the vehicle on a hoist and make sure the vehicle is level.
• Visually inspect for the following:
- Exhaust leaks at flanges and gaskets.
- HO2S-22 not torqued to specification.
- Physical exhaust system concerns.
- Aftermarket exhaust.
- Punctures or cracks in the catalyst.
• Where any of the above conditions or concerns found during inspection?
Yes
Repair or replace malfunctioning part, then go to Step 12.
No
Go to the next step.
7
CHECK HO2S-22 CIRCUIT FOR SHORT TO VPWR AND GROND
• Disconnect PCM and HO2S-22.
• Measure the resistance between following terminals at PCM harness side connector.
- Between terminal 61 and battery negative post
- Between terminal 61 and 71, 91, 96
• Is the resistance greater than 10,000 ohms?
Yes
Go to the next step.
No
Repair for short circuit, then go to Step 12.
8
CHECK HO2S-22 SIGNAL CIRCUIT AND HO2S-22 SIGNAL RETURN CIRCUITS FOR OPEN IN HARNESS
• Measure resistance following at harness side connector.
- Between HO2S-22 terminal 2 and PCM terminal 96
- Between HO2S-22 terminal 3 and PCM terminal 91
- Between HO2S-12 terminal 4 and PCM terminal 61
- Between HO2S-22 terminal 1 and PCM terminal 71
• Is the resistance less than 5.0 ohms?
Yes
Go to the next step.
No
Repair for open circuit, then go to Step 12.
9
CHECK HO2S-22 CIRCUIT VOLTAGE
• Connect PCM and HO2S-22.
• Connect the WDS or equivalent to DLC.
• Start the engine.
• Access HO2S22 PID.
• Is the voltage greater than 1.5 V?
Yes
Go to Step 11.
No
Go to the next step.
10
HO2S-22 CIRCUIT CHECK
• Connect PCM.
• HO2S-22 disconnected.
• Jumper terminal 2 and 3 at HO2S-22 harness side connector.
• Turn the ignition switch to ON.
• Access HO2S22 PID.
• Is the HO2S22 PID value greater than 1.5 V?
Yes
Replace HO2S-22, then go to Step 12.
No
Replace PCM, then go to Step 12.
11
CHECK FOR OVER VOLTAGE ON HO2S-12 CIRCUIT IN PCM
• Turn the ignition switch to ON.
• HO2S-22 disconnected.
• Measure voltage for following:
- Between terminal 3 at HO2S-22 harness side connector and battery negative post.
- Between terminal 4 at HO2S-22 harness side connector and battery negative post.
• Is the voltage greater than 1.5 V?
Yes
Replace PCM, then go to the next step.
No
Replace HO2S-22, then go to the next step.
12
VERIFY TROUBLESHOOTING OF DTC P2273 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform KOER self test.
• Is the PENDING CODE same DTC present?
Yes
Replace PCM, then go to the next step.
No
Go to the next step.
13
VERIFY AFTER REPAIR PROCEDURE
• Perform "AFTER REPAIR PROCEDURE".
• Is there any DTC present?
Yes
Go to applicable DTC inspection.
No
Troubleshooting completed.