P0506

DTC P0506

CIRCUIT DESCRIPTION
The throttle actuator control (TAC) motor is controlled by the engine control module (ECM). The DC motor located in the throttle body drives the throttle plate. In order to decrease idle speed, the ECM commands the throttle closed, which reduces air flow into the engine. In order to increase idle speed, the ECM commands the throttle plate open, which allows more air flow into the engine. 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 P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0270, P0271, P0273, P0274, P0276, P0277, P0279, P0280, P0282, P0283, P0351, P0352, P0353, P0354, P0355, P0356, P0357, P0358, P0638, P1106, P1107, P2100, P2101, P2108, P2119, P2122, P2123, P2127, P2128, P2135, P2138, or P2176 are not set.
- The engine is operating.
- The engine coolant temperature (ECT) is more than -7°C (+19°F).
- The ECT is less than 120°C (248°F).
- The vehicle speed is 0 km/h (0 mph).
- DTC P0506 runs continuously once the above conditions are met.

CONDITIONS FOR SETTING THE DTC
- The actual idle speed is 100 RPM lower than the desired idle speed.
- The above condition is present for more than 10 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

Step 1 - Step 5:

The number below refers to the step number on the diagnostic table.
2. This test determines whether the engine can achieve the commanded RPM.