Buick Regal: DTC P0506 or P0507
Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
- Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
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
- DTCs P0068, P0101, P0102, P0103, P0112, P0113, P0117, P0118, P0121,
P0122, P0123, P0171,
P0172, P0174, P0175, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268.
P0270, P0271,
P0273, P0274, P0276, P0277, P0300 - P0306, P0351 - P0356, P0461 - P0464,
P0496, P0627,
P0628, P0629, P0722, P1516, P2066 - P2068, are not set.
- The barometric pressure (BARO) is greater than 70 kPa.
- The engine coolant temperature (ECT) is greater than 60ºC (140ºF).
- The engine run time is greater than 60 s.
- The ignition voltage is between 11 - 32 V.
- The transmission is not changing gears.
- The torque converter clutch (TCC) is not changing states.
- The intake air temperature (IAT) is warmer than -20ºC (-4ºF).
- The vehicle speed is less than 3 km/h (2 mph).
- The commanded engine speed is steady within 25 RPM.
- The engine is idling for greater than 5 s.
- The DTCs run when the above conditions are met.
Conditions for Setting the DTC
P0506
The actual engine speed is 94 RPM less than the desired idle speed for 10 s.
P0507
The actual engine speed is 188 RPM greater than the desired idle speed for 10
s.
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 Wiring Schematics (LTG)
Connector End View Reference
Component Connector End View Index
Description and Operation
Throttle Actuator Control (TAC) System Description
Electrical Information Reference
- Circuit Testing
- Connector Repairs
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify there are no other DTCs set.
- If any other DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further
diagnosis.
- Go to next step: If no other DTCs are set
3. Verify the scan tool Throttle Body Idle Airflow Compensation parameter is
less than 90 %.
Refer to Throttle Body Cleaning.
- Go to next step: If less than 90 %
4. Engine Idling at the normal operating temperature.
5. Verify the actual Engine Speed is not 100 RPM less than the Desired Idle
Speed.
- If 100 RPM less than the Desired Idle Speed
Refer to Circuit/System Testing.
- Go to next step: If 100 RPM greater than the Desired Idle Speed
6. Verify the actual Engine Speed is not 200 RPM greater than the Desired
Idle Speed.
- If 200 RPM greater than the Desired Idle Speed
Refer to Circuit/System Testing.
- Go to next step: If 200 RPM less than the Desired Idle Speed
7. 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
data.
8. Verify the DTC does not set.
Refer to Circuit/System Testing.
- Go to next step: If the DTC does not set
9. All OK
Circuit/System Testing
P0506
- Verify the conditions listed below do not exist.
- Restricted exhaust
- Mechanical conditions that limits engine speed
- Parasitic load on the engine - For example, a transmission
condition, a belt driven accessory
condition.
- If a condition is found
Repair as necessary.
- Go to next step: If a condition is not found
2. All OK.
P0507
1. Verify the conditions listed below do not exist.
- Vacuum leaks
- A throttle valve that does not close correctly
- Verify the correct operation of the crankcase ventilation system.
Inspect for the conditions
listed below:
- Improper routing of the positive crankcase ventilation (PCV) system
- Vacuum leaks in the PCV system - Refer to Crankcase Ventilation
System
- Inspection/Diagnosis.
- If a condition is found
Repair as necessary.
- Go to next step: If a condition is not found
2. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
Throttle Body Assembly Replacement.
READ NEXT:
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diag
SEE MORE:
Diagnostic Instructions
Perform the Diagnostic System Check prior to using this diagnostic
procedure: Diagnostic
System Check - Vehicle
Review the description of Strategy Based Diagnosis: Strategy Based
Diagnosis
An overview of each diagnostic category can be found here: Diagnostic
Proced
Diagnostic Instructions
Perform the Diagnostic System Check - Vehicle prior to using this
diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic
approach.
Diagnostic Procedure Instructions provides an overview of each
diagnostic category.
DTC Descriptors
D