P1506 FORD, JAGUAR, LINCOLN, MAZDA, MERCURY: IDLE AIR CONTROL OVERSPEED ERROR
POST UPDATED IN February, 2023
P1506 FORD, JAGUAR, LINCOLN, MAZDA, MERCURY: IDLE AIR CONTROL OVERSPEED ERROR
The Idle Air Control (IAC) Valve assembly is intended to control engine idle speed and provide a dash function. This assembly measures the intake air passing around the throttle plate through a bypass, which is located on the inside of the IAC Valve assembly and throttle body.
The PCM (Powertrain Control Module) determines the expected idle speed or bypass air. It signals the IAC assembly using a certain duty cycle. In response, the valve is moved to a position that allows the amount of bypass air to be regulated. This controller also monitors the engine rpm and accordingly increases or decreases the valve duty cycle to achieve the desired rpm.
The P1506 OBDII diagnostic code P1506 is stored after the PCM detects an engine idle speed, which exceeds the expected revolutions. This error can be defined as the engine’s idle speed being out of specification.
Reasons for setting the P1506 OBD2 DTC P1506 OBD2 code:
Steps to solve the P1506 OBDII fault code: