DTC Troubleshooting: P0506
DTC P0506: Idle Control System RPM Lower Than Expected
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
P0506 Idle Control System RPM Lower Than Expected
    

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Start the engine.

?4.
Hold the engine speed at 3,000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on, then let it idle at least 20 seconds.

?5.
Check for these conditions in the DATA LIST with the HDS.
Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
IAT SENSOR (1) above 32 °F (0 °C)
VEHICLE SPEED is 0 mph (0 km/h)
AF FB (ST FUEL TRIM) between 0.69 and 1.47
FSS is CLOSED

Signal
Current conditions
Values
Unit
ECT SENSOR 1
    
IAT Sensor (1)
    
VEHICLE SPEED
    
AF FB (ST FUEL TRIM)
    
FSS
    

?6.
Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
DTC Description
OBD STATUS
P0506 Idle Control System RPM Lower Than Expected
  

Does the HDS indicate FAILED?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
If the HDS indicates PASSED, go to step 3. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 1-5 and recheck.
2.
Throttle body visual check:

Throttle body visual check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Remove the intake air duct from the throttle body.

?3.
Check for dirt, carbon, or damage in the throttle bore.

Is there dirt, carbon, or damage in the throttle bore?

     
YES
     
     
     
If there is dirt or carbon, clean the throttle body. Also check for damage to the air cleaner element. If there is damage in the throttle bore, replace the throttle body.?
     
NO
     
     
     
The throttle body is OK. Check the A/C system, then go to step 4.
3.
Throttle body visual check:

Throttle body visual check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Remove the intake air duct from the throttle body.

?3.
Check for dirt, carbon, or damage in the throttle bore.

Is there dirt, carbon, or damage in the throttle bore?

     
YES
     
     
     
If there is dirt or carbon, clean the throttle body. Also check for damage to the air cleaner element. If there is damage in the throttle bore, replace the throttle body.?
     
NO
     
     
     
The throttle body is OK. Go to step 4.
4.
Idle control system check:

Idle control system check
?1.
Reinstall the intake air duct.

?2.
Turn the vehicle to the ON mode.

?3.
Clear the DTC with the HDS.


?4.
Start the engine.

?5.
Hold the engine speed at 3,000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on, then let it idle at least 20 seconds.

?6.
Check for these conditions in the DATA LIST with the HDS.
Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
IAT SENSOR (1) above 32 °F (0 °C)
VEHICLE SPEED is 0 mph (0 km/h)
AF FB (ST FUEL TRIM) between 0.69 and 1.47
FSS is CLOSED

Signal
Current conditions
Values
Unit
ECT SENSOR 1
    
IAT Sensor (1)
    
VEHICLE SPEED
    
AF FB (ST FUEL TRIM)
    
FSS
    

?7.
Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS.
DTC Description
OBD STATUS
P0506 Idle Control System RPM Lower Than Expected
  

Does the HDS indicate PASSED?

     
YES
     
     
     
     
NO
     
     
     
If the HDS indicates FAILED, check the A/C system, then recheck. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION, go to step 4-6 and recheck.?