Remember when you didn't need a computer science degree from the Massachusetts Institute of Technology (MIT) to actively diagnose automotive issues? If something was wrong, you just tinkered with the parts.
Sure, maybe we're over-exaggerating, but most new cars are, essentially, computers. They contain on-board diagnostic (OBD) systems that monitor the performance of major components and generate trouble codes to indicate if something has gone awry.
Diagnostic trouble codes (DTCs) are how an On-Board Diagnostic II system pinpoints and transmits issues to automotive technicians, so it’s essential that technicians be able to understand the codes to quickly identify the problem to minimize associated downtime.
How to Read DTC Codes
The first number in the DTC lets you know whether it’s specific to the vehicle manufacturer or an SAE generic code that applies to all OBD II systems. The last three numbers provide information regarding the specific vehicle circuit and system. See the image below for an analysis of a typical OBD II code.
OBD II DTC Codes List
Standard trouble codes start with P, then a four-digit numeric code. See the table below for a few common vehicle error codes and what they signify:
|
DTC Codes |
Description |
Common Codes Within This Range |
|
P0100-P0199 — Fuel and Air Metering |
These codes are used to monitor the fuel and air ratio of the vehicle's engine to determine if an oxygen sensor is failing, plus they will monitor a vehicle's emissions and fuel economy. |
|
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P0200-P0299 — Fuel and Air Metering (Injector Circuit) |
These codes are going to involve fuel injectors. |
|
|
P0300-P0399 — Ignition System or Misfire |
These codes will trigger if there are issues with the car's ignition. For example, if there are spark plug issues. |
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|
P0400-P0499 — Auxiliary Emissions Controls |
These codes will determine issues with the system's EVAP (evaporative emission control) systems. The EVAP's function is to prevent gas fumes from reaching the atmosphere, thus keeping air pollution to a minimum. |
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P0500-P0599 — Vehicle Speed Controls and Idle Control System |
These codes will monitor the vehicle's speed controls and idling. Issues from the vehicle speed sensor (VSS) will trigger these codes. |
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P0600-P0699 — Computer Output Circuit |
These codes will be triggered by a faulty computer system. |
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P0700-P0899 — Transmission and Beyond |
These codes monitor the system's transmissions. Most of the time, the code is triggered by a fault in the system's transmission computer. |
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It's essential to have the proper tools to test and diagnose a vehicle's on-board problem.
Accurate diagnosis is key to repair based on manufacturer suggestions. Being able to identify these OBD trouble codes will lead to decreased downtime and higher productivity.
TPC Wire & Cable® offers a vast selection of automotive wire, cord, and automotive cable accessories. Let's start the conversation today about how we can reduce your downtime and costs.
