Acura RL. Manual - part 836

1. Disconnect the ECPS control unit 12P connector.  

2. Turn the ignition switch ON (II).  

3. Measure the voltage between ECPS control unit 12P connector terminal No. 8 and body ground. 

Fig. 163: Measuring Voltage Between ECPS Control Unit 12P Connector Terminal No. 8 And 
Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there about 5 V?  

YES - Go to step 4. 

NO - Repair open in the wire between the ECPS control unit and the gauge assembly module. 

4. Connect ECPS control unit 12P connector terminal No. 8 and body ground with a jumper wire. 

Fig. 164: Connecting ECPS Control Unit 12P Connector Terminal No. 8 And Body Ground 
With Jumper Wire 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Does the ECPS indicator go off?  

YES - Go to step 5. 

NO - Do the troubleshooting for the gauge control module (see GAUGE CONTROL MODULE 
INPUT TEST ). 

5. Disconnect the jumper wire.  

 

2007 Acura RL 

2005-08 STEERING Steering - RL

  

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6. Measure the voltage between body ground and ECPS control unit 12P connector terminal No. 7. 

Fig. 165: Measuring Voltage Between Body Ground And ECPS Control Unit 12P Connector 
Terminal No. 7 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there battery voltage?  

YES - Go to step 7. 

NO - Repair open in the wire between the ECPS control unit 12P connector and the under-dash 
fuse/relay box. 

7. Check for voltage between body ground and the ECPS control unit 12P connector terminal No. 9. 

Fig. 166: Checking Voltage Between Body Ground And ECPS Control Unit 12P Connector 
Terminal No. 9 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there less than 0.1 V?  

YES - Go to step 8. 

NO - Repair open in the wire between the ECPS control unit 12P connector and body ground (G203). 

8. Check for resistance between ECPS control unit 12P connector terminals No. 2 and No. 5, No. 6, No. 

11, and No. 12 individually. 

 

2007 Acura RL 

2005-08 STEERING Steering - RL

  

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Fig. 167: Checking Resistance Between ECPS Control Unit 12P Connector Terminals No. 2 And 
No. 5, No. 6, No. 11, And No. 12 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is the resistance between 19.8 to 24.2 ohms (at 20°C, 68°F)?  

YES - Go to step 9. 

NO - Check for and repair open/short in the wires between the ECPS control unit 12P connector and 
the stepping valve motor. If the wires are OK, the ECPS valve is faulty; replace the ECPS valve. 

9. Start the engine.  

10. Measure the voltage between ECPS control unit 12P connector terminal No. 4 and body ground. 

Fig. 168: Measuring Voltage Between ECPS Control Unit 12P Connector Terminal No. 4 And 
Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there about 5.0 V?  

YES - Check for loose connector terminals in the ECPS control unit 12P connector and repair if 
necessary. If the terminals are OK, replace the ECPS control unit (see ECPS CONTROL UNIT 
REMOVAL/INSTALLATION ). 

NO - Repair open in the GRN wire between the ECPS control unit and PCM connector A. 

ECPS indicator comes on while driving the vehicle (but the ECPS indicator goes off after the engine is restarted) 

 

2007 Acura RL 

2005-08 STEERING Steering - RL

  

me 

 

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Repair open in the BLU wire between the ECPS control unit 12P connector and PCM connector A (31P), or 
repair the poor connection in the ECPS circuit. 

ECPS indicator comes on, but there is no power assist 



Hard steering  



Uneven or rough steering  

1. Turn the ignition switch ON (II). 

Is there a clicking noise from the ECPS valve for 2 to 3 seconds?  

YES - The ECPS system is OK at this time. Go to SYMPTOM TROUBLESHOOTING . 

NO - Faulty ECPS control unit or the ECPS valve, replace the ECPS control unit (see ECPS 
CONTROL UNIT REMOVAL/INSTALLATION ) or the valve housing and stepping valve motor 
(see STEERING GEARBOX OVERHAUL ). 

ECPS CONTROL UNIT REMOVAL/INSTALLATION 

1. Remove the driver's dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER 

REMOVAL/INSTALLATION ), and the driver's dashboard lower cover (see DRIVER'S 
DASHBOARD LOWER COVER REMOVAL/INSTALLATION ).  

2. Disconnect the connector (A) from the ECPS control unit, and remove the bolt (B). 

Fig. 169: Identifying ECPS Control Unit Connector And Fastener With Torque Specifications 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

3. Install the ECPS control unit in the reverse order of removal. 

 

2007 Acura RL 

2005-08 STEERING Steering - RL

  

me 

 

Friday, June 05, 2009 2:20:16 PM

Page 98 

© 2005 Mitchell Repair Information Company, LLC.