To get a code digit: There’s a 2 second pause between digits and 4 second pause between codes. It may take patience to do so but doable.
If you don’t have a code-scanner, you can count the signals and find the codes that way. Counting Digits to Get Your Trouble Codes You can easily grab your trouble codes, and this will help you diagnose your MIL or “Check engine ” light on that fox body Mustang of yours! Note: Make sure your engine is warmed up before doing these tests.
The small pigtail is the self test input (STI).
The large connector contains the self test output (STO) and ground (SIG RTN). The fox Mustang’s EEC IV computer has two connectors for self-testing and located on the driver-side firewall.
