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Home >> Cadillac >> 2005 >> XLR >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls (DTC P0341 To P0629) >> DTC P0506 >> Test Description
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Test Description

The number below refers to the step number on the diagnostic table.

  1. 2:  This test determines whether the engine can achieve the commanded RPM.
DTC P0506

Step Action Yes No
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1 Did you perform the Diagnostic System Check - Vehicle? Go to Step 2  Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2 
  1. Start the engine.
  2. Command the engine speed up to 1,500 RPM, down to 500 RPM, and up to 1,500 RPM, with a scan tool
  3. Exit the RPM control function.
Does the actual engine speed correspond to the desired engine speed, within 100 RPM, with each command?		 Go to Intermittent Conditions Go to Step 3 
3 Inspect for any condition that can reduce idle speed by increasing engine load. Examples include:
  • Incorrect torque converter clutch (TCC) operation
  • Accessories that require additional torque to operate
  • Restricted exhaust
  • Mechanical conditions that limit engine speed

Did you complete the action?		 Go to Step 4  -
4
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition?		 Go to Step 2  Go to Step 5 
5 Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed?		 Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information System OK
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