DTC/HO2S Reference List:
Key on, engine off.
Select Generic OBD II Function from the menu and trigger.
Select Diagnostic Monitoring Test Results from the menu and trigger.
Scroll to Test ID: 01 trigger and press start.
Fuel calculations can be affected by unmetered 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.
Vacuum lines disconnected.
Improperly seated engine oil dipstick, tube, and oil fill cap.
Exhaust leaks at flanges and gaskets.
Note: Refer to the PCM connector pin number in the beginning of this pinpoint test.
Disconnect suspect HO2S.
Check for water contamination.
Jumper HO2S signal to VPWR at the HO2S harness connector.
Note: HO2S displayed as O2S on Scan Tool.
Access the correct HO2S PID.
Note: If viewing the HO2S11 (O2S11) PID on the 2.3L Focus, the engine must be running.
Visually inspect the HO2S circuit for exposed wiring, water contamination, corrosion and proper assembly.
Measure resistance of HO2S SIG circuit between PCM harness connector pin and HO2S harness connector.
Measure resistance of HO2S SIG RTN circuit between PCM harness connector pin and HO2S harness connector.
Measure resistance between the HO2S SIG and VPWR circuit at the PCM harness connector pin.
Investigate the following items as potential sources of HO2S contamination:
Use of unapproved silicon sealers.
Fuel contaminated by silicon additives.
Excessive oil burning (i.e. rings, valve seals and oil overfill).
Glycol (antifreeze) leaking internally in the engine.
Lead contaminated fuel.
Short drive cycles in cold weather.
Use of unapproved cleaning agents.
Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
Measure resistance of the HO2S SIG circuit and HO2S Signal Return circuit between the PCM harness connector pin and the HO2S harness connector.
Drive Cycles Description of OBD II Drive Cycle
The following procedure is designed to execute and complete the OBDII monitors and to clear the Ford P1000, I/M readiness code. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the "OBDII Monitor Exercised" column. When the ambient air temperature is outside 4.4 to 37.8°C (40 to 100 °F), or the altitude is above 2438 meters (8000 feet), the EVAP monitor will not run. If the P1000 code must be cleared in these conditions, the PCM must detect them once (twice on some applications) before the EVAP monitor can be "bypassed" and the P1000 cleared. The EVAP "bypassing" procedure is described in the following drive cycle.
The OBDII Drive Cycle will be performed using a scan tool. Consult the instruction manual for each described function
Drive Cycle Recommendations
Most OBDII monitors will complete more readily using a "steady foot" driving style during cruise or acceleration modes. Operating the throttle in a "smooth" fashion will minimize the time required for monitor completion.
Fuel tank level should be between 1/2 and 3/4 fill with 3/4 fill being the most desirable.
The Evaporative Monitor can only operate during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize "fuel slosh".
WARNING: STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN PROCEEDING THROUGH THE FOLLOWING DRIVE CYCLES.
For best result, follow each of the following steps as accurately as possible:
Hi you will need a scanner and run done the problem you have using the pinpoint test provided if you don't have one I recommend that you take it to a repair shop that does to find the problem without a scanner it will be hard to dianois . you will be just throwing parts at it thanks