Fast Codes

1991 Mercury Tracer Base, 4D Sedan, AutomaticSECTION Fast Codes
WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 1992 Mercury Tracer, 1992 Mercury Topaz, 1992 Mercury Sable, 1992 Mercury Grand Marquis, and 1992 Mercury Cougar. However, it is still accessible from the selected car via links, so may be relevant.

At start of KOEO SELF-TEST and after Wide Open Throttle (WOT) request in KOER SELF-TEST, ECA outputs short bursts of information, known as FAST CODES, which were used by manufacturer during assembly. With most equipment, these code bursts are not visible; an entire code sequence lasts less than 1/2 second. If this fluctuation is visible on test equipment, ignore it.

Fig 1: Reading Service Codes (Typical)
G90E10946Courtesy of FORD MOTOR CO.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.