Acura RL. Manual - part 771

13. Raise the vehicle speed to 19 mph (30 km/h).  

14. Measure the voltage between SH-AWD control unit connector terminals A5 and A13. 

Fig. 141: Measuring Voltage Between SH-AWD Control Unit Connector Terminals A5 And A13
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Does the voltage change when the propeller shaft is rotated?  

YES - Replace the SH-AWD control unit (see SH-AWD CONTROL UNIT REPLACEMENT ). 

NO - Go to step 15. 

15. Turn the ignition switch OFF.  

16. Disconnect the hypoid gear speed sensor 3P connector.  

17. Turn the ignition switch ON (II).  

18. Measure the voltage between hypoid gear speed sensor 3P connector terminals No. 1 and No. 3. 

Fig. 142: Measuring Voltage Between Hypoid Gear Speed Sensor 3P Connector Terminals No. 1 
And No. 3 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there 4.0 V or more?  

YES - Go to step 19. 

NO - Go to step 22. 

19. Turn the ignition switch OFF.  

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

me 

 

Friday, June 05, 2009 3:02:19 PM

Page 111  © 2005 Mitchell Repair Information Company, LLC. 

20. Disconnect SH-AWD control unit connector A (26P).  

21. Check for continuity between SH-AWD control unit connector terminal A2 and hypoid gear speed 

sensor 3P connector terminal No. 2. 

Fig. 143: Checking Continuity Between SH-AWD Control Unit Connector Terminal A2 And 
Hypoid Gear Speed Sensor Terminal No. 2 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES - Replace the hypoid gear speed sensor (see HYPOID GEAR SPEED SENSOR 
REPLACEMENT ). 

NO - Repair open in the wire between SH-AWD control unit connector A and the hypoid gear speed 
sensor connector. 

22. Turn the ignition switch OFF.  

23. Disconnect SH-AWD control unit connector A (26P).  

24. Check for continuity between SH-AWD control unit connector terminal A18 and hypoid gear speed 

sensor 3P connector terminal No. 1. 

Fig. 144: Checking Continuity Between SH-AWD Control Unit Connector Terminal A18 And 
Hypoid Gear Speed Sensor Terminal No. 1 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

me 

 

Friday, June 05, 2009 3:02:19 PM

Page 112  © 2005 Mitchell Repair Information Company, LLC. 

YES - Go to step 25. 

NO - Repair open in the wire between SH-AWD control unit connector A and the hypoid gear speed 
sensor connector. 

25. Check for continuity between SH-AWD control unit connector terminal A5 and hypoid gear speed 

sensor 3P connector terminal No. 3. 

Fig. 145: Checking Continuity Between SH-AWD Control Unit Connector Terminal A5 And 
Hypoid Gear Speed Sensor Terminal No. 3 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES - Replace the SH-AWD control unit (see SH-AWD CONTROL UNIT REPLACEMENT ). 

NO - Repair open in the wire between SH-AWD control unit connector A and the hypoid gear speed 
sensor connector. 

DTC 78-XX (78-3 TO 78-23): SH-AWD CONTROL UNIT SELF-DIAGNOSTIC MALFUNCTION 

1. Turn the ignition switch ON (II).  

2. Make sure the HDS communicates with the vehicle and the SH-AWD control unit. If it doesn't, 

troubleshoot the DLC circuit; '05-07 models (see '05-07 MODELS ), '08 model (see '08 MODEL ).  

3. Clear the DTC with the HDS.  

4. Turn the ignition switch OFF.  

5. Turn the ignition switch ON (II).  

6. Check for DTCs with the HDS. 

Is DTC 78-xx indicated?  

YES - Replace the SH-AWD control unit (see SH-AWD CONTROL UNIT REPLACEMENT ). 

NO - Intermittent failure, the system is OK at this time.

NOTE:

Before you troubleshoot, review the general troubleshooting information 
(see GENERAL TROUBLESHOOTING INFORMATION ).

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

me 

 

Friday, June 05, 2009 3:02:19 PM

Page 113  © 2005 Mitchell Repair Information Company, LLC. 

DTC 81-1: LEFT SEARCH COIL SENSOR MALFUNCTION

1. Turn the ignition switch ON (II).  

2. Make sure the HDS communicates with the vehicle and the SH-AWD control unit. If it doesn't, 

troubleshoot the DLC circuit; '05-07 models (see '05-07 MODELS ), '08 model (see '08 MODEL ).  

3. Clear the DTC with the HDS.  

4. Turn the ignition switch OFF.  

5. Turn the ignition switch ON (II).  

6. Check for DTCs with the HDS. 

Is DTC 81-1 indicated?  

YES - Replace the rear differential side case (see SIDE CASE REPLACEMENT ). 

NO - Intermittent failure, the system is OK at this time. 

DTC 81-2: LEFT SEARCH COIL SENSOR (OPEN OR SHORT) 

1. Turn the ignition switch ON (II).  

2. Make sure the HDS communicates with the vehicle and the SH-AWD control unit. If it doesn't, 

troubleshoot the DLC circuit; '05-07 models (see '05-07 MODELS ), '08 model (see '08 MODEL ).  

3. Turn the ignition switch OFF.  

4. Disconnect SH-AWD control unit connector A (26P).  

5. Check for continuity between SH-AWD control unit connector terminals A4 and A17. 

Fig. 146: Checking Continuity Between SH-AWD Control Unit Connector Terminals A4 And 
A17 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

NOTE:

Before you troubleshoot, review the general troubleshooting information 
(see GENERAL TROUBLESHOOTING INFORMATION ).

NOTE:

Before you troubleshoot, review the general troubleshooting information 
(see GENERAL TROUBLESHOOTING INFORMATION ).

 

2007 Acura RL 

2005-08 DRIVELINE/AXLES Rear Differential - RL

  

me 

 

Friday, June 05, 2009 3:02:19 PM

Page 114  © 2005 Mitchell Repair Information Company, LLC.