What does it mean when an OBD fault causes torque limitation?

1 Answers
MacColin
07/30/25 5:35am
OBD system continuously monitors the engine's operating conditions to check if the vehicle's exhaust exceeds the standard. If it does, a warning will be issued immediately. Here are the specific details about the OBD system: 1. Introduction: OBD stands for On-Board Diagnostics, which is a detection system extended for automotive fault diagnosis. 2. Working principle: The OBD system continuously monitors the engine's operating conditions to check if the vehicle's exhaust exceeds the standard. If it does, a warning will be issued immediately. When a fault occurs in the system, the Malfunction Indicator Lamp (MIL) or Check Engine warning light will illuminate, and the Powertrain Control Module (PCM) will store the fault information in memory. The fault code can be read from the PCM through a specific procedure. Based on the fault code, maintenance personnel can quickly and accurately determine the nature and location of the fault. 3. Scope of monitoring: The OBD system monitors the engine, catalytic converter, particulate trap, oxygen sensor, emission control system, fuel system, EGR system, and other components in real-time. It then connects to the ECU through various emission-related component information.
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