How do I know if my car computer is unrepairable?

The modern automobile is becoming the epitome of technological innovation. And when you need auto repair work, you may find that one of your computer modules is damaged. In most cases, a bad computer is unrepairable and needs to be replaced. Let’s discuss this in greater detail below.

ECUs, PCMs, BCMs, and TCMs

There are four key types of computer modules that are found in modern automobiles. While there may be other computer modules, such as the ICM (Ignition Control Module), these usually are less complex than the other types. PCM stands for Powertrain Control Module. ECU stands for Engine Control Unit. TCM stands for Transmission Control Module. And BCM stands for Body Control Module.

These modules are typically accessible with a computer interface to read various DTCs (Diagnostic Trouble Codes) when malfunctions occur in your vehicle. When these faults occur, you may see your “Check Engine light” illuminate or flash. A PCM may control the engine and automatic transmission at the same time. Many of the codes that are stored in these devices are manufacturer specific and require expensive diagnostic computers to interact with the modules.

Determining Damage to a Module

When a computer in your vehicle is damaged and unrepairable, you won’t be able to access it with a code reader. In most cases, the vehicle will also suffer from a no-start problem. An ABS (Anti-lock Brake System) control module can also cause similar problems. Because these modules all work together, if one is bad, it can cause the entire system to fail.

You can usually purchase junk parts instead of paying $1000 or more for new modules from the dealer. If you do purchase junk parts, however, make sure that you always get the TCM and ECU from the same vehicle to ensure compatibility. You usually have to replace these two modules in tandem to complete the auto repair.