Acura RL. Manual - part 97

DTC P2610: POWERTRAIN CONTROL MODULE (PCM) INTERNAL POWER OFF TIMER 
MALFUNCTION 

Fig. 304: Powertrain Control Module (PCM) Circuit Diagram 

General Description 

The powertrain control module (PCM) has a built-in power off timer that measures the duration of time the 
ignition switch is off. This measurement is used for evaporative emission (EVAP) leak detection and 
temperature assumption of the catalytic converter. 

The CPU in the PCM accesses the power off timer when reading the measured duration. When the access 
process fails, a malfunction is detected and a DTC is stored. When an abnormality is found in the read data, 
a malfunction is detected and a DTC is stored. 

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

MONITOR DESCRIPTION CHART 

Enable Conditions 

ENABLE CONDITIONS 

Malfunction Threshold 

The access process to the power off timer fails, or a malfunction is found in the read data for at least 10 
seconds. 

Diagnosis Details 

Execution

Continuous

Sequence

None

Duration

10 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

Condition

 

Ignition switch

ON

(1)

(1)

Ignition switch on when a battery is disconnected and connected again is excluded.

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

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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 P2627 (155): ADVANCED DIAGNOSTICS 

DTC P2627: REAR AIR/FUEL RATIO (A/F) SENSOR (BANK 1, SENSOR 1) LABEL CIRCUIT 
LOW VOLTAGE 

Fig. 305: Rear Air/Fuel Ratio (A/F) Sensor (Bank 1, Sensor 1) LABEL Circuit Diagram (Low 
Voltage) 

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.

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:08 PM

Page 386  © 2005 Mitchell Repair Information Company, LLC. 

The rear A/F sensor (bank 1, sensor 1) has a built-in LABEL resistance to regulate the difference of the 
sensor characteristics. The PCM reads the resistance to regulate the difference properly. If the LABEL 
resistance (VLBLB1 signal voltage) is a set value or less, the PCM detects a malfunction and stores a DTC. 

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

MONITOR DESCRIPTION CHART 

Enable Conditions 

ENABLE CONDITIONS 

Malfunction Threshold 

The VLBLB1 voltage is 0.3 V or less for at least 5 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 P2628 (155): ADVANCED DIAGNOSTICS 

DTC P2628: REAR AIR/FUEL RATIO (A/F) SENSOR (BANK 1, SENSOR 1) LABEL CIRCUIT 
HIGH VOLTAGE 

Execution

Continuous

Sequence

None

Duration

5 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

Condition

 

Ignition switch

ON

No active DTCs

P0135, P2195, P2237, P2238, P2243, P2245, P2251, P2252, P2628

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:08 PM

Page 387  © 2005 Mitchell Repair Information Company, LLC. 

Fig. 306: Rear Air/Fuel Ratio (A/F) Sensor (Bank 1, Sensor 1) LABEL Circuit (High Voltage) 

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. 

The rear A/F sensor (bank 1, sensor 1) has a built-in LABEL resistance to regulate the differences of the 
sensor characteristics. The PCM reads the resistance to regulate the difference properly. If the LABEL 
resistance (VLBLB1 signal voltage) is a set value or more, 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

5 seconds or more

DTC Type

One drive cycle, MIL ON

OBD Status

N/A

 

2007 Acura RL 

2007 ENGINE PERFORMANCE Advanced Diagnostics - RL

  

me 

 

Friday, June 05, 2009 2:32:08 PM

Page 388  © 2005 Mitchell Repair Information Company, LLC.