Archives: DTC Codes

What Does Code P0790 Mean? The OBD-II diagnostic trouble code P0790, which translates to “Normal/Performance Switch Circuit Malfunction,” indicates that the Powertrain Control Module (PCM) or Transmission Control Module (TCM) has detected an electrical fault within the circuit of a driver-selectable “Normal/Performance” mode switch. This switch typically allows the driver to toggle between different vehicle […]

What Does Code P0801 Mean? The OBD-II diagnostic trouble code P0801 signifies a “Reverse Inhibit Control Circuit Malfunction.” This code is set when the Powertrain Control Module (PCM), or in some applications the Transmission Control Module (TCM), detects an electrical anomaly within the circuit responsible for controlling or monitoring the reverse gear inhibit function. The […]

What Does Code P0803 Mean? DTC P0803 indicates a 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction. This code is specifically associated with vehicles equipped with manual transmissions that utilize a “skip shift” or “Computer Aided Gear Selection” (CAGS) system, commonly found in performance-oriented vehicles like certain Corvettes, Camaros, and Vipers. The purpose of the […]

What Does Code P0804 Mean? DTC P0804 signifies a detected malfunction within the 1-4 Upshift (Skip Shift) Lamp Control Circuit. This code is specifically associated with vehicles equipped with a Computer Aided Gear Selection (CAGS) or “skip shift” system, predominantly found on certain manual transmission performance vehicles (e.g., Corvette, Camaro, Viper). The CAGS system is […]

What Does Code P1100 Mean? The diagnostic trouble code P1100, categorized as a manufacturer-specific code, primarily indicates an issue with the Mass Air Flow (MAF) sensor circuit, often specifically an intermittent or erratic signal, or that the MAF monitor self-test has not completed its diagnostic cycle within the Engine Control Module (ECM) or Powertrain Control […]

What Does Code P1101 Mean? DTC P1101, primarily observed in Ford, Lincoln, Mercury, and Mazda vehicles utilizing Ford powertrain architectures, signifies that the Powertrain Control Module (PCM) or Engine Control Module (ECM) has detected an anomaly with the Mass Air Flow (MAF) sensor’s signal during a self-test, specifically the Key On Engine Running (KOER) diagnostic […]

What Does Code P1102 Mean? DTC P1102 signifies that the Engine Control Module (ECM), often referred to as the Powertrain Control Module (PCM), has detected a Mass Air Flow (MAF) sensor reading that is within its expected operational voltage or frequency range, yet is consistently and significantly lower than the value the ECM calculates it […]

What Does Code P1103 Mean? DTC P1103 signifies “MAF Sensor In Range But Higher Than Expected.” This diagnostic trouble code indicates that the Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected an inconsistency where the Mass Airflow (MAF) sensor is reporting an airflow value that is plausible (within its normal operating voltage […]

What Does Code P1104 Mean? Diagnostic Trouble Code (DTC) P1104 is a manufacturer-specific code, commonly observed in General Motors (GM) vehicles, indicating an issue with the Mass Air Flow (MAF) sensor’s ground circuit integrity. The Engine Control Module (ECM), also known as the Powertrain Control Module (PCM), relies on the MAF sensor to accurately measure […]

What Does Code P1105 Mean? DTC P1105 specifically indicates a malfunction within the primary or “upper” alternator circuit in a vehicle equipped with a dual alternator system. The Engine Control Module (ECM) or Powertrain Control Module (PCM) continuously monitors the charging system’s performance, including the voltage output and load characteristics of both alternators. In a […]