Function Inspection Using M-MDS

P2251: 00 (PCM (H3T)) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION Record the freeze frame data/snapshot data. NOTE: Recording can be facilitated using the screen capture function of the PC.	-	Go to the next step.
2	PURPOSE: INSPECT WIRING HARNESS (INCLUDING CONNECTOR/TERMINAL) BETWEEN A/F SENSOR AND PCM FOR MALFUNCTION Inspect the applicable circuit. (See CIRCUIT INSPECTION .) (See CONNECTOR INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification 1.
3	PURPOSE: DETERMINE INTEGRITY OF A/F SENSOR Start the engine and warm it up completely. Display the PCM PID [A/F_SEN_CUR] using the M-MDS. (See PID/DATA MONITOR INSPECTION .) Drive the vehicle under the following conditions. WARNING: Observe legal speed limits when driving the vehicle and perform the procedure in a location where safety can be assured. To prevent an accident, work with another person when the vehicle is being driven (one person drives vehicle, other person operates M-MDS). After increasing the engine speed to 3, 000 rpm, decelerate using engine braking. Is the displayed PID value as follows? A/F_SEN_CUR: 0.25 mA or more	Yes	Go to Troubleshooting Diagnostic Procedure to perform the repair completion verification 1.
3		No	Go to the next step.
4	PURPOSE: VERIFY CONNECTOR CONNECTIONS Display the PCM PID [A/F_SEN_CUR] using the M-MDS. (See PID/DATA MONITOR INSPECTION .) Does the PID value fluctuate when the following connectors are shaken? A/F sensor PCM	Yes	Repair or replace the applicable wiring harness or connector parts. Go to Troubleshooting Diagnostic Procedure to perform the repair completion verification 1.
4		No	Replace the A/F sensor. (Refer to [AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION ] in service information). Go to Troubleshooting Diagnostic Procedure to perform the repair completion verification 1.