GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Express - AWD 🢒 Engine 🢒 Engine Controls and Fuel - 4.8L, 5.3L, and 6.0L 🢒 DTC P0506

DTC P0506 With Throttle Actuator Control

Circuit Description

The Electronic Throttle Control (ETC) System uses various inputs from the powertrain control module (PCM). This system uses the inputs to control the idle speed through serial data circuits to the throttle actuator control (TAC) module. The DC motor, which is located on the throttle body, activates the throttle plate. In order to decrease idle speed, the TAC module commands the throttle closed, reducing air flow into the engine, and the idle speed decreases. In order to increase the idle speed, the TAC module commands the throttle plate open, allowing more air in order to bypass the throttle plate. If the actual idle RPM does not match the desired idle RPM within a calibrated time, DTC P0506 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0506 Idle Speed Low

Conditions for Running the DTC
    • DTCs P0101-P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0120, P0125, P0171, P0172, P0174, P0175, P0200, P0220, P0300, P0440, P0442, P0443, P0496, P0500, P0502, P0503, P2135 are not set.
    • The engine is running for more than 60 seconds.
    • The engine coolant temperature (ECT) is more than 60°C (140°F).
    • The intake air temperature (IAT) is more than -10°C (+14°F).
    • The barometric pressure (BARO) is more than 65 kPa.
    • The system voltage is between 9-18 volts.
    • The vehicle speed is less than 1.7 km/h (1 mph).
    • The accelerator pedal position (APP) sensor is at 0 percent.
    • DTC P0506 runs continuously once the above conditions are met.

Conditions for Setting the DTC

The PCM detects that the actual idle speed is 100 RPM less than the desired idle speed for 5 continuous seconds.

Action Taken When the DTC Sets
    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC
    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Test Description

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

  1. This test determines if the engine can achieve the commanded RPM.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Component Views or Powertrain Control Module Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Apply the park brake.
  2. Block the drive wheels.
  3. Start the engine.
  4. Turn OFF all accessories.
  5. Command the engine RPM to 1,500 RPM, to 500 RPM, and back to 1,500 RPM with the RPM control function of the scan tool.
  6. Exit the RPM Control function.

Did the engine speed stay within 100 RPM of the commanded RPM during the above test?

Go to Step 3

Go to Step 4

3
  1. Observe the Freeze Frame/Failure Records for this DTC.
  2. Turn OFF the ignition for 30 seconds.
  3. Use the following information to operate the vehicle under the conditions which set the DTC:
    4. • The data in the Freeze Frame/Failure Records
    • The parameters listed in the Conditions for Running in the DTC

Does the DTC set?

Go to Step 4

Go to Testing for Intermittent Conditions and Poor Connections

4

Inspect for the following conditions:

    • Deposits in the throttle body
    • Objects which are blocking the air intake system
    • Energy-draining load on the engine, such as transmission conditions

Did you find and correct the condition?

Go to Step 5

--

5
  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 6

6

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

System OK