P2228

DTC P2228: Barometric Pressure Circuit Low Input

Barometric Pressure Sensor Circuit:

CIRCUIT OPERATION
- A 5-volt voltage is supplied to the barometric pressure sensor power terminal (terminal No.1) from the ECM (terminal No.42). The ground terminal (terminal No.5) is grounded with ECM (terminal No.34).
- A voltage that is proportional to the atmospheric pressure is sent to the ECM (terminal No.51) from the barometric pressure sensor output terminal (terminal No.2).

TECHNICAL DESCRIPTION
- The barometric pressure sensor outputs a voltage which corresponds to the barometric pressure.
- The ECM checks whether this voltage is within a specified range.

DESCRIPTIONS OF MONITOR METHODS
- Barometric pressure sensor output voltage is out of reasonable barometric pressure range.

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)
- Not applicable

Sensor (The sensor below is determined to be normal)
- Not applicable

DTC SET CONDITIONS

Logic Flow Chart:

Logic Flow Chart

Check Conditions
- 2 seconds or more have passed since the engine starting sequence was completed.
- Battery positive voltage is higher than 8 volts.

Judgment Criterion
- Barometric pressure sensor output has continued to be 49 kPa (14.5 in.Hg) or lower approximately 15,000 ft above sea level for 10 seconds.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 23. OBD-II Drive Cycle Pattern Lists

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Barometric pressure sensor failed.
- Open or shorted barometric pressure sensor circuit, harness damage, or connector damage.
- ECM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B

STEP 1. Using scan tool MB991958, check data list item 25: Barometric Pressure Sensor.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991958 to the data reading mode for item 25, Barometric Pressure Sensor.
- When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg).
- When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg).
- When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 in.Hg).
- When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 in.Hg).

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES: It can be assumed that this malfunction is intermittent.

NO: Go to Step 2.

STEP 2. Measure the sensor output voltage at barometric pressure sensor connector B-105 by backprobing.

1. Do not disconnect connector B-105.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal No.2 and ground by backprobing.
- When altitude is 0 m (0 foot), voltage should measure 3.7 and 4.3 volts.
- When altitude is 600 m (1,969 feet), voltage should measure 3.4 and 4.0 volts.
- When altitude is 1,200 m (3,937 feet), voltage should measure 3.2 and 3.8 volts.
- When altitude is 1,800 m (5,906 feet), voltage should measure 2.9 and 3.5 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?

YES: Go to Step 3.

NO: Go to Step 7.

STEP 3. Measure the sensor output voltage at ECM connector C-119 by backprobing.

1. Do not disconnect connector C-119.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal No.51 and ground by backprobing.
- When altitude is 0 m (0 foot), voltage should measure between 3.7 and 4.3 volts.
- When altitude is 600 m (1,969 feet), voltage should measure between 3.4 and 4.0 volts.
- When altitude is 1,200 m (3,937 feet), voltage should measure between 3.2 and 3.8 volts.
- When altitude is 1,800 m (5,906 feet), voltage should measure between 2.9 and 3.5 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?

YES: Go to Step 4.

NO: Go to Step 6.

STEP 4. Check harness connector B-105 at the barometric pressure sensor and harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 5.

NO: Repair or replace it. Then go to Step 18.

STEP 5. Using scan tool MB991958, check data list item 25: Barometric Pressure Sensor.

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.

STEP 6. Check harness connector B-105 at the barometric pressure sensor and harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Repair harness wire between barometric pressure sensor connector B-105 (terminal No.2) and ECM connector C-119 (terminal No.51) because of open circuit or harness damage. Then go to Step 18.

NO: Repair or replace it. Then go to Step 18.

STEP 7. Measure the sensor supply voltage at barometric pressure sensor connector B-105 by backprobing.

1. Do not disconnect connector B-105.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal No.1 and ground by backprobing.
- Voltage should be between 4.8 and 5.2 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage between 4.8 and 5.2 volts?

YES: Go to Step 12.

NO: Go to Step 8.

STEP 8. Measure the sensor supply voltage at ECM connector C-119 by backprobing.

1. Do not disconnect connector C-119.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal No.42 and ground by backprobing.
- Voltage should be between 4.8 and 5.2 volts.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage between 4.8 and 5.2 volts?

YES: Go to Step 9.

NO: Go to Step 10.

STEP 9. Check harness connector B-105 at the barometric pressure sensor and harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Repair harness wire between barometric pressure sensor connector B-105 (terminal No.1) and ECM connector C-119 (terminal No.42) because of open circuit or harness damage. Then go to Step 18.

NO: Repair or replace it. Then go to Step 18.

STEP 10. Check harness connector B-105 at the barometric pressure sensor and harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 11.

NO: Repair or replace it. Then go to Step 18.

STEP 11. Check for short circuit to ground between barometric pressure sensor connector B-105 (terminal No.1) and ECM connector C-119 (terminal No.42).

Q: Is the harness wire in good condition?

YES: Replace the ECM. Then go to Step 18.

NO: Repair it. Then go to Step 18.

STEP 12. Measure the ground voltage at barometric pressure sensor connector B-105 by backprobing.

1. Do not disconnect connector B-105.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal No.5 and ground by backprobing.
- Voltage should be 0.5 volt or less.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage 0.5 volt or less?

YES: Go to Step 15.

NO: Go to Step 13.

STEP 13. Check harness connector B-105 at the barometric pressure sensor and harness connector C-121 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 14.

NO: Repair or replace it. Then go to Step 18.

STEP 14. Check for harness damage between barometric pressure sensor connector B-105 (terminal No.5) and ECM connector C-121 (terminal No.34).

Q: Is the harness wire in good condition?

YES: Replace the ECM. Then go to Step 18.

NO: Repair it. Then go to Step 18.

STEP 15. Check harness connector B-105 at barometric pressure sensor for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 16.

NO: Repair or replace it. Then go to Step 18.

STEP 16. Check harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 17.

NO: Repair or replace it. Then go to Step 18.

STEP 17. Check for short circuit to ground and harness damage between barometric pressure sensor connector B-105 (terminal No.2) and ECM connector C-119 (terminal No.51).

Q: Is the harness wire in good condition?

YES: Replace the volume airflow sensor. Then go to Step 18.

NO: Repair it. Then go to Step 18.

STEP 18. 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 23. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P2228 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.