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Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 1472 (Engine Control System - Diagnosis - 4.2L (DTC P0140 To DTC P0506)) >> Diagnosis >> DTC P0506 >> Test Description

Test Description

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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. If the engine does not reach the commanded RPMs, the test determines whether the RPM is too high or too low.
DTC P0506

Step Action Yes No
Schematic Reference:  Engine Controls Schematics 
Connector End View Reference:  Powertrain Control Module (PCM) Connector End Views  or  Engine Controls Connector End Views 
1 Did you perform the Diagnostic System Check-Engine Controls? Go to Step 2  Go to Diagnostic System Check - Engine Controls
  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 engine speed correspond, 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 System OK