Archives: DTC Codes

What Does Code P0602 Mean? DTC P0602 signifies an internal control module programming error within the Powertrain Control Module (PCM) or Engine Control Module (ECM). This code indicates that the PCM/ECM has detected an inconsistency, corruption, or failure in its internal software, calibration data, or non-volatile memory. Essentially, the module’s core operating instructions, which dictate […]

What Does Code P0603 Mean? DTC P0603 signifies an Internal Control Module Keep Alive Memory (KAM) Error. The Keep Alive Memory, often referred to as non-volatile RAM, is a critical section within the Engine Control Module (ECM) or Powertrain Control Module (PCM) that retains learned adaptive parameters and operational strategies even when the vehicle’s ignition […]

What Does Code P0604 Mean? DTC P0604 signifies an internal malfunction within the vehicle’s primary control unit, specifically the Engine Control Module (ECM), also commonly referred to as the Powertrain Control Module (PCM). The code indicates an “Internal Control Module Random Access Memory (RAM) Error.” RAM is a critical volatile memory component within the ECM […]

What Does Code P0605 Mean? DTC P0605 signifies an Internal Control Module Read Only Memory (ROM) Error. The Engine Control Module (ECM) or Powertrain Control Module (PCM), the central processing unit of the vehicle’s engine management system, contains various types of memory. ROM, or Read-Only Memory, is a non-volatile memory that stores the foundational operating […]

What Does Code P0606 Mean? The diagnostic trouble code P0606 indicates an internal fault within the Powertrain Control Module (PCM), which may also be referred to as the Engine Control Module (ECM) or Engine Control Unit (ECU). This code is triggered when the PCM’s primary microprocessor, or a critical auxiliary processor responsible for monitoring the […]

What Does Code P0608 Mean? The diagnostic trouble code P0608 signifies that the Powertrain Control Module (PCM), which often integrates the Engine Control Module (ECM) and Transmission Control Module (TCM) functionalities, has detected an internal anomaly or an electrical circuit malfunction within its dedicated output signal path for Vehicle Speed Sensor (VSS) data, specifically identified […]

What Does Code P0609 Mean? The OBD-II diagnostic trouble code P0609, which stands for Control Module VSS Output “B” Malfunction, indicates that the Engine Control Module (ECM), also commonly referred to as the Powertrain Control Module (PCM), has detected an inconsistency or an outright failure in a specific vehicle speed sensor (VSS) output signal from […]

What Does Code P0620 Mean? DTC P0620 signifies a detected malfunction within the Generator Control Circuit. In contemporary automotive charging systems, the Engine Control Module (ECM) or Powertrain Control Module (PCM) plays a critical role in actively regulating the generator’s (alternator’s) output voltage and current. Unlike older systems where an external or internal voltage regulator […]

What Does Code P0621 Mean? The OBD-II diagnostic trouble code P0621 stands for “Generator Lamp “L” Control Circuit Malfunction.” This code specifically indicates that the Powertrain Control Module (PCM) or Engine Control Module (ECM) has detected an anomaly within the control circuit dedicated to the generator (alternator) warning lamp, often referred to as the “L” […]

What Does Code P0622 Mean? The diagnostic trouble code P0622, “Generator Field ‘F’ Control Circuit Malfunction,” indicates that the Powertrain Control Module (PCM) or Engine Control Module (ECM) has detected an electrical fault within the circuit responsible for controlling the alternator’s field windings. The ‘F’ typically refers to the field circuit, which is crucial for […]