Acura RL. Manual - part 86

Fig. 276: Barometric Pressure Sensor (Low Voltage) - Circuit Diagram

Fig. 277: Barometric Pressure Sensor Output Voltage Graph 

General Description 

The barometric pressure (BARO) sensor is built into the powertrain control module (PCM) and monitors 
atmospheric pressure. The PCM estimates appropriate intake airflow from the manifold absolute pressure 
(MAP) sensor output voltage and BARO sensor output voltage. If the BARO sensor output voltage is a 
specified value or less, the PCM detects a malfunction and a DTC is stored. 

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

MONITOR DESCRIPTION CHART 

Enable Conditions 

ENABLE CONDITIONS 

Malfunction Threshold 

The BARO sensor output voltage is 1.58 V or less for at least 2 seconds. 

Diagnosis Details 

Execution

Continuous

Sequence

None

Duration

2 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

Condition

 

Ignition switch

ON

No active DTCs

P1109, P2229

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

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Conditions for illuminating the MIL 

When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the 
PCM memory. 

Conditions for clearing the MIL 

The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the 
diagnostic runs. 

The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by 
disconnecting the battery. 

DTC P2229 (13): ADVANCED DIAGNOSTICS 

DTC P2229: BAROMETRIC PRESSURE (BARO) SENSOR CIRCUIT HIGH VOLTAGE 

Fig. 278: Barometric Pressure Sensor (High Voltage) - Circuit Diagram 

Fig. 279: Barometric Pressure Sensor Output Voltage Graph 

General Description 

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:07 PM

Page 342  © 2005 Mitchell Repair Information Company, LLC. 

The barometric pressure (BARO) sensor is built into the powertrain control module (PCM) and monitors 
atmospheric pressure. The PCM estimates appropriate intake airflow from the manifold absolute pressure 
(MAP) sensor output voltage and BARO sensor output voltage. If the BARO sensor output voltage is a 
specified value or more, the PCM detects a malfunction and a DTC is stored. 

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

MONITOR DESCRIPTION CHART 

Enable Conditions 

ENABLE CONDITIONS 

Malfunction Threshold 

The BARO sensor output voltage is 4.49 V or more for at least 2 seconds. 

Diagnosis Details 

Conditions for illuminating the MIL 

When a malfunction is detected, the MIL comes on and the DTC and the freeze frame data are stored in the 
PCM memory. 

Conditions for clearing the MIL 

The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the 
diagnostic runs. 

The MIL, the DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by 
disconnecting the battery. 

DTC P2237 (155): ADVANCED DIAGNOSTICS 

DTC P2237: REAR AIR/FUEL RATIO (A/F) SENSOR (BANK 1, SENSOR 1) IP CIRCUIT HIGH 
VOLTAGE 

Execution

Continuous

Sequence

None

Duration

2 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

Condition

 

Ignition switch

ON

No active DTCs

P1109, P2228

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:07 PM

Page 343  © 2005 Mitchell Repair Information Company, LLC. 

Fig. 280: Rear Air/Fuel Ratio Sensor (Bank 1, Sensor 1) - Circuit Diagram 

General Description 

The rear air/fuel ratio (A/F) sensor (bank 1, sensor 1) is installed in the exhaust manifold and detects oxygen 
content in the exhaust gas. The rear A/F sensor transmits a signal to the powertrain control module (PCM). 
The PCM controls fuel injection duration by comparing the target air/fuel ratio with the rear A/F sensor 
signal. The sensor includes the VS cell, the pump cell, the atmospheric reference cavity, the diffusion layer, 
and the heater, and it enables overall feedback control. 

If the IPB1 terminal voltage is out of a specified range, the PCM detects a malfunction and stores a DTC. 

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

MONITOR DESCRIPTION CHART 

Enable Conditions 

ENABLE CONDITIONS 

Execution

Continuous

Sequence

None

Duration

15 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Condition

Minimum

Maximum

VSB1 terminal voltage

3.4 V

4.8 V

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:07 PM

Page 344  © 2005 Mitchell Repair Information Company, LLC.