P2197
DTC P2197: Cylinder 2, 3 Heated Oxygen Sensor (front) Inactive
CAUTION:
If DTC P2197 has been set, TCL related DTC U1120 is also set. After P2197 has been diagnosed, don't forget to erase DTC U1120.
TECHNICAL DESCRIPTION
- The ECM [M/T] or the PCM [A/T] effects air/fuel ratio feedback control in accordance with the signals from the cylinder 2, 3 heater oxygen sensor (front).
- If the cylinder 2, 3 heated oxygen sensor (front) has deteriorated, corrections will be made by the cylinder 2, 3 heated oxygen sensor (rear).
- DTC P2197 becomes stored in memory if a failure is detected in the cylinder 2, 3 heated oxygen sensor (front).
DESCRIPTIONS OF MONITOR METHODS
Cylinder 2, 3 heated oxygen sensor (front) output voltage does not cross lean/rich criteria (about 0.5 volt) within specified period.
MONITOR EXECUTION
Continuous
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Heated oxygen sensor (front) monitor
- Misfire monitor
Sensor (The sensor below is determined to be normal)
- Engine coolant temperature sensor
- Intake air temperature sensor
DTC SET CONDITIONS
Logic Flow Chart
Check Conditions
- 128 seconds or more have passed since the engine starting sequence was completed.
- Engine coolant temperature is 7°C (45° F) or more.
- Under the closed loop air/fuel ratio control.
- Intake air temperature is more than -10°C (14° F).
Judgement Criterion
- Cylinder 2, 3 heated oxygen sensor (front) output voltage is less than lean/rich criteria (about 0.5 volt) for 128 seconds.
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22 Monitors, Trips, Drive Cycles and Readiness Codes .
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are: )
- Cylinder 2, 3 heated oxygen sensor (front) deteriorated.
- ECM failed. [M/T]
- PCM failed. [A/T]
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991910: Main Harness A
- MB991316: Test Harness
STEP 1. Check the cylinder 2, 3 heated oxygen sensor (front).
(1)Disconnect the cylinder 2, 3 heated oxygen sensor (front) connector B-35 and connect test harness special tool MB991316, to the connector on the cylinder 2, 3 heated oxygen sensor (front) side.
(2)Warm up the engine until engine coolant temperature reaches 80°C (176°F) or higher.
(3)Rev the engine for 5 minutes or more with the engine speed of 2,500 r/min.
(4)Connect a digital voltage meter between terminal No. 2 (black clip) and terminal No. 4
(white clip).
(5)While repeatedly revving the engine, measure the cylinder 2, 3 heated oxygen sensor
(front) output voltage.
Standard value: 0.6 - 1.0 V
CAUTION:
- Be very careful when connecting the jumper wires; incorrect connection can damage the heated oxygen sensor.
- Be careful the heater can be damaged if a voltage beyond 8 volts is applied to the heated oxygen sensor heater.
NOTE:
If the temperature of sensing area does not reach the high temperature [of approximately 400°C (752°F) or more] even through the heated oxygen sensor is normal, the output voltage would be possibly low in spite of the rich air-fuel ratio. Therefore, if the output voltage is low, use a jumper wire to connect the terminal No. 1 (red clip) and the terminal No. 3 (blue clip) of the heated oxygen sensor with the positive terminal and the negative terminal of 8 volts power supply respectively, then check again.
Q. Is the measured voltage between 0.6 and 1.0 volt?
YES Go to Step 2.
NO Replace the cylinder 2, 3 heated oxygen sensor (front). Then go to Step 3.
STEP 2. Test the OBD-II drive cycle.
(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22 Monitors, Trips, Drive Cycles and Readiness Codes.
(2)Check the diagnostic trouble code (DTC).
Q. Is DTC P2197 set?
YES Replace the ECM or the PCM. When the ECM or the PCM is replaced, register the encrypted code. Immobilizer System.
Then go to Step 3.
NO It can be assumed that this malfunction is intermittent.
STEP 3. Test the OBD-II drive cycle.
(1)Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 22 Monitors, Trips, Drive Cycles and Readiness Codes.
(2)Check the diagnostic trouble code (DTC).
Q. Is DTC P2197 set?
YES Retry the troubleshooting.
NO The inspection is complete.