1991 Nissan-Datsun Sentra SE-RFACTORY OEM SERVICE PROCEDURE

System Testing: Maxima

Warm engine to operating temperature. Engage A/C clutch using A/C switch in passenger compartment. Both cooling fans should run at low speed. Disconnect coolant temperature sensor connector. Both cooling fans should run at high speed. If not, check power supplies, grounds, relays, radiator fan switches and motors. If no faults are found, check component wiring. See Figure .

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.