Experience Recognized Something Unusual

The truck had already received an engine control computer before arriving at MDC Automotive Repair.

Yet when we connected our diagnostic equipment, we found eight active injector circuit trouble codes—even though the engine was running.

We also noticed that the scan-tool parameter identification data, commonly called PIDs, was displayed in an unusual order.

After years of working as a Gold Certified Technician, Mike recognized that something wasn't right with the information being reported.

That experience gave us a direction to investigate, but it wasn't enough by itself to condemn the computer.

We performed pinpoint testing of the engine management system and determined that the PCM was faulty.

After receiving authorization, we installed and programmed a replacement PCM.

The injector circuit codes disappeared, and the scan-tool PIDs returned to their expected order.

Experience helped us recognize the abnormal behavior. Testing established the failure.

But the transmission code remained.

That meant we had corrected one problem, not the entire complaint.

Our investigation continued.