1982 Mercury LN7 Automatic TransFACTORY OEM SERVICE PROCEDURE

Speed Sensor (Exc. Electronic Speedometer)

Disconnect speed sensor connector and connect an ohmmeter between wire connector terminals (Dk Grn/White stripe and Black) at speed sensor end. A reading of 30-100 ohms (40 ohms for Escort and Lynx) should be obtained. A reading of 0 ohms indicates a shorted coil, and a high reading indicates an open coil. If reading is within proper range and speedometer operates properly, sensor is probably good. Substitute a new sensor if necessary to check operation.

Factory Service Tools

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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.

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