1988 Cadillac Seville BaseFACTORY OEM SERVICE PROCEDURE

ECM Input Code EI79 - Cruise Control Enable On/Off Input: Notes

The cruise control enable switch provides power to the cruise enable input of the ECM. The ECM cannot allow cruise control operation until the enable or instrument panel switch is turned to the "ON" position, which passes 12 volts to ECM pin "C12".

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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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.