Think it's a sencor
I'm assuming you mean "won't" crank - if so its either a bad starter, starter solenoid or faulty battery
When turning the key to the "start" position is it totally dead? Meaning the engine will not spin at all? If so, check the voltage of the battery with a multimeter, should read about 12.4 volts. If low, charge with a battery charger. A decent charger should indicate the amperage present in the battery. If it is well below the cold cranking amperage rating of the battery, it's probably shot, but try to charge it anyway. Charging is not a quick process. May take a few hours.
If battery is fully charged, check battery cables including the one at the starter for looseness or corrosion. If everything is cleaned and tight, try jumping starter solenoid, if voltage is present and still doesn't crank, replace starter
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