Diagnostic Instructions
DTC Descriptors
DTC P0506: Idle Speed Low
DTC P0507: Idle Speed High
Circuit/System Description
The throttle actuator control (TAC) motor is a DC motor that is part of the throttle body assembly. The TAC motor drives the throttle valve. The engine control module (ECM) controls the TAC motor based on throttle position sensor input. The idle speed
is controlled by the ECM based on various inputs. The ECM commands the TAC motor to open or close the throttle valve in order to maintain the desired idle speed.
Conditions for Running the DTC
| • | The engine run time is greater than 60 seconds. |
| • | The evaporative emission (EVAP) purge flow is less than 100 percent. |
| • | The barometric pressure (BARO) is greater than 72 kPa. |
| • | The intake air temperature (IAT) is greater than -20°C (-4°F). |
| • | The engine coolant temperature (ECT) is greater than 60°C (+140°F). |
| • | The ignition voltage is between 11-16 volts. |
| • | The DTCs run when the above conditions are met for 3 seconds. |
Conditions for Setting the DTC
P0506
The actual engine speed is less than the desired idle speed by at least 100 RPM for 10 seconds.
P0507
The actual engine speed is greater than the desired idle speed by at least 200 RPM for 10 seconds.
Action Taken When the DTC Sets
DTCs P0506, and P0507 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0506, and P0507 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References
for scan tool information
Circuit/System Verification
- Allow the engine to idle within the conditions for running the DTCs for 1 minute. DTCs P0506 or P0507 should not set.
- Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
P0506
| • | Inspect the engine for vacuum leaks. |
| • | Inspect the throttle valve for the correct operation. A throttle valve that does not close correctly sets this DTC. |
| • | Verify the correct operation of the crankcase ventilation system. Inspect for the following conditions: |
| - | The routing of the positive crankcase ventilation (PCV) system |
| - | Vacuum leaks in the PCV system |
P0507
| • | Inspect for excess deposits in the throttle body. |
| • | Inspect for a parasitic load on the engine--For example, a transmission condition, a belt driven accessory condition. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
