What Does P0637 Mean? The P0637 code is a generic OBD-II trouble code that signals a problem with the power steering control circuit. The power steering control circuit sends data to the powertrain control module (PCM), and many of the other control modules, such as the transmission control module, traction control module, and fuel injection control module, and the cruise control module. When the PCM or one of these other control modules detects an issue with the powers steering control circuit, the P0637 trouble code will be triggered. engine code P0637P0637 fixobd P0637dtc P0637obd code P0637obd2 P0637P0637 car codediagnostic code P0637car code P0637check engine code P0637fehlercode P0637P0637 fiatcodigo P0637codigo falla P0637P0637 kody b??dówcodigo de falla P0637 What are the common causes of P0637 ? Defective ECU strategies or components will prevent proper regeneration The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture. An air leak forward of the DPF will change the sensor readings resulting in the code How do you troubleshoot P0637 ? The engine system, in conjuction with the engine control module (ECM)/powertrain control module (PCM), activates the P0637 code solenoid valve to control oil pressure to the engine mechanism that is installed in the valve system to switch valve timing between Low and High.If the engine solenoid valve has an open or short circuit, a DTC is stored. Searches related to P0637 Code - Power Steering Control Circuit High P0637 P0637