What Are Detroit Diesel Fault Codes?

A Detroit Diesel fault code indicates a specific problem with a Detroit Diesel Series 60 engine. The fault code is displayed when the “check engine” light is activated on a truck powered by the aforementioned engine.

The Detroit Diesel Series 60 is an inline-6 four-cycle diesel engine that was first produced in 1987. The most popular on-highway version was the 12.7-liter, which was electronically controlled by the Detroit Diesel Electronic Control system. The DDEC system was designed to be particularly easy to operate and provide an owner, dealer or operator with a variety of diagnostic functions, including the ability to download periodic engine management reports.

The list of fault codes begins with number 11, indicating “VSG Sensor Input Voltage Low,” and runs through number 86, indicating “External Pump Pressure Sensor Input Voltage Low.” Codes 43 (Low Coolant), 44 (Oil or Coolant High Temperature), 45 (Low Oil Pressure), 51 (EEPROM Error) and 53 (EEPROM Non-Volatile Memory Failure) are critical codes. If one of these codes is shown, a yellow light will come on to indicate a significant engine fault, and the engine may shut down. All other codes will cause a yellow light to come on, indicating a minor fault, but allow the engine to continue running.