Acura RL. Manual - part 743

Fig. 17: Checking Continuity Between RFC Unit 1P Connector Terminal And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES - Go to step 47. 

NO - Repair open in the wire between the RFC unit relay (+B line) and the RFC unit, then go to step 
52. 

47. Remove the jumper wire from the RFC unit relay 4P connector.  

48. Jump the SCS line with the HDS.  

49. Disconnect PCM connector A (31P).  

50. Connect RFC unit relay 4P connector terminal No. 1 and body ground with a jumper wire. 

Fig. 18: Connecting RFC Unit Relay 4P Connector Terminal No. 1 And Body Ground With 
Jumper Wire 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

51. Check for continuity between PCM connector terminal A13 and body ground. 

Fig. 19: Checking Continuity Between PCM Connector Terminal A13 And Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES - Go to step 58. 

NO - Repair open in the wire between the PCM (A13) and the RFC unit relay, then go to step 52.

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE Radiator Fan Control (RFC) System - RL

  

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© 2005 Mitchell Repair Information Company, LLC. 

52. Turn the ignition switch OFF.  

53. Reconnect all connectors.  

54. Turn the ignition switch ON (II).  

55. Reset the PCM with the HDS.  

56. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).  

57. Check for Temporary DTCs or DTCs with the HDS. 

Is DTC P0480 indicated?  

YES - Check for poor connections or loose terminals at the RFC unit, the RFC unit relay, the radiator 
fan motor, the condenser fan motor, and the PCM. 

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the 
indicated DTCs troubleshooting. 

58. Reconnect all connectors.  

59. Update the PCM if it does not have the latest software (see UPDATING THE PCM ), or substitute a 

known-good PCM (see SUBSTITUTING THE PCM ).  

60. Check for Temporary DTCs or DTCs with the HDS. 

Is DTC P0480 indicated?  

YES - Check for poor connections or loose terminals at the RFC unit, the RFC unit relay, the radiator 
fan motor, the condenser fan motor, and the PCM. If the PCM was updated, substitute a known-good 
PCM (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, go to step 1. 

NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the 
original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, 
go to the indicated DTCs troubleshooting.

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE Radiator Fan Control (RFC) System - RL

  

me 

 

Friday, June 05, 2009 2:37:42 PM

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© 2005 Mitchell Repair Information Company, LLC. 

2005-08 DRIVELINE/AXLES

Rear Differential - RL 

SPECIAL TOOLS 

Fig. 1: Identifying Special Tools 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

COMPONENT LOCATION INDEX

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

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Fig. 2: Identifying Rear Differential Component Location 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

GENERAL TROUBLESHOOTING INFORMATION 

SH-AWD INDICATOR 

The SH-AWD indicator comes on under certain conditions even if the AWD system is working normally. 
Here are some examples: 



When you use high-powered wireless equipment such as a CB or Ham radio in the vehicle.  



When you keep spinning the rear wheels while the vehicle is stuck in sand, mud, snow, etc.  



When the battery voltage suddenly drops below 8 volts or rises above 16 volts.  

After the SH-AWD indicator comes on, it stays on until you turn the ignition switch off. 

DIAGNOSTIC TROUBLE CODE (DTC) 



The SH-AWD control unit can memorize up to seven different DTCs. The system displays the DTCs 
by blinking the SH-AWD indicator. Multiple DTCs are displayed in the order they occurred, 
beginning with the most recent.  



If the same DTC is detected more than once, the most recent DTC is written over the earlier one. 
Therefore, when the same problem is detected more than once, it is memorized as a single DTC.  



The DTCs are memorized in the EEPROM (non-volatile memory). Therefore, the memorized DTCs 

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

me 

 

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© 2005 Mitchell Repair Information Company, LLC.