LEMON Manuals: Even more car manuals for everyone
Home >> Mercury >> 2009 >> Sable Premier, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1255 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P0412: - Secondary Air Injection (Air) System - Switching Valve A Circuit

DTC P0412: - Secondary Air Injection (Air) System - Switching Valve A Circuit

WARNING: This page does not describe the selected car, but rather 32 other vehicles, including the 2009 Mercury Mountaineer, 2009 Mercury Milan, 2009 Mercury Mariner, 2009 Mercury Grand Marquis, and 2009 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0412: - SECONDARY AIR INJECTION (AIR) SYSTEM - SWITCHING VALVE A CIRCUIT

Description:  On the primary side of the AIR relay, open and short faults on the AIR command circuit are detected during normal operation by the powertrain control module (PCM) output driver.
Possible Causes: 
  • Short to voltage or ground in the AIR command circuit
  • Open in the AIR command circuit
  • AIR bypass solenoid fault
  • AIR relay fault
Diagnostic Aids:  For intermittent faults use the AIR PCM output driver fault PID (AIRF) during a harness wiggle test with the AIR PCM output driver in OFF and ON states. The AIR PCM output driver fault PID AIRF instantly detects open circuits and shorts to ground with the PCM output driver off. The AIR PCM output driver fault PID AIRF instantly detects open circuits and shorts to ground with the PCM output driver off. The AIR PCM output driver fault PID AIRF instantly detects a short to voltage or low resistance load with the PCM output driver on. Use the OUTPUT TEST MODE (OTM) to toggle the PCM output driver from OFF to ON.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to Pinpoint Test HM .