DTC Advanced Diagnostics: P0506 (2.0L Engine) (2024 2025)
DTC P0506 : Idle Control System RPM Lower Than Expected
General Description
The idle speed control system matches desired and current engine idle speed. Therefore, an integral action controller is used. In case of a permanent difference between desired and current engine idle speed, the diagnosis checks if this difference is out of a calibrated range with the integral action controller. If current engine speed deviation occurs, the powertrain control module (PCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 8 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Engine coolant temperature [ECT Sensor 1] | -22 deg.F (-30 deg.C) | 289.9 deg.F (143.3 deg.C) |
| Intake air temperature [IAT Sensor (1)] | -23.4 deg.F (-30.8 deg.C) | - |
| Other | Vehicle speed [Vehicle Speed] is at 0 mph (0 km/h) | |
[ ]: HDS Parameter
Malfunction Threshold
The set point idle speed minus the current idle speed is higher than 100 rpm.
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Throttle body air leak
- Intake manifold air leak
- Intake air system air leak
- PCM internal circuit failure
Confirmation Procedure
Operating Condition
- Start the engine. Hold the engine speed [Engine Speed] at 3, 000 rpm without load (in neutral) until the radiator fan comes on.
- Let the engine idle for a while.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.