WONT START, BATTERY READING 12.5 V, TURN IGNITION KEY ON AND NOTHING HAPPENS

You need a volt meter the problem is some ware between the battery and the ignition switch .Check battery grounds all if bat is grounded you should have 6.5 v D.C from B+ to anything on the engine or frame one at a time then test both for 13 v at the same time jump them together .This could be your problem 2 battery's with 1 bad ground .Then start from the other end the ignition switch use jumper leads hook to the switch in start position key turned to black to ground see what you have for voltage drop it should be around 12 volts if you have nothing its the ignition switch if you have less then 12 v its likely a bad ground from one of the battery's or something related to the drive motor

6 Common Reasons Your Car Won't Start ' General ...

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Jun 25, 2015 - If no dashboard lights come on when you turn the key in the ignition, that's a ... You can also check whether your windshield wipers, radio, heat/AC or headlights work. ... If your car can't pump the gas to fuel the engine, it won't start. ...the starter works and the fuel gets to the engine, but still nothing happens.

Three Reasons Why Your Car May Not Start

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Your online resource for auto, truck or motorcycle insurance. ... Starting Problem # 1: Engine Won't Crank At All. Scenario: You turn the key, but nothing happens: And by nothing, we mean there ... Jump-starting the battery should get the engine to start. ... Incars with electronic fuel injection, you should hear a light hum a few ...

Car Won't Start ' The Family Handyman

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If you turn the car key and your car won't start, don't give up. Before you call for a tow, try these seven simple tricks to get your car started again. The only tool ... To heat up the battery, terminals and starter, try the "key cycling" trick (photo 1). But if the domelight stayed bright when you turned the key, move on to the next trick.

How to Diagnose Problems If Your Car Won't Start - For ...

Check signal wire from starter to either solenoid or start relay. Make sure signal wire is connected to starter properly. One side of the start relay leads to the starter the other to the ignition switch. Check sinal wire is connected. If so test signal wire w/ tester. Ohms setting. Test relay ohms setting. Relays usualy dont go bad. Test ignition switch w/ tester. DC voltage 12 volts or greater. Black terminal to neg or ground. Red terminal to ignition switch side of relay/solenoid. Turn ignition swich to start look for voltage reading. Depending on the vehicle it could be anywhere from 6 to 12 volts. If no voltage reading somthing has failed on the ignition switch side of relay. A relay is simalar to a fuse and will be housed w other fuses under the hood. Also all fuses should be checked. This can be done w the ohms setting on tester without removing the fuse. Look at the top of the fuse there are exposed points that allow the tip of each lead to contact the fuse. Only some fuses are like this. Remember signal wire or fuses this is probably going to be your problem.

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The vehicle is having problems reading the tiny metal security slug in the ignition key. When you used a key to unlock the door, you disabled the security system so it started. There are a variety of different resistance values on the slugs in the key. You can have someone with a ohm meter read the resistance of yours and install a fixed resistor of the same identical value to the wiring for the key security system. You may alternatively spray contact cleaner or a bit of WD-40 in the ignition switch to clean it off. Insert and remove the key several times, wiping it off each time you remove it.

could be the starter relay or a bad power wire. or the wire that goes from ignition switch to starter relay has just fallen off. to start I would put a volt meter test the voltage at both ends of the relay while you turn the key. you have a positive in from battery wish should always read 12 volts, the other big wire goes to the starter that should only show 12 volts while key is in the start position. there should be at least one small wire on the relay that is a the power soulse coming from ignition when the small wire sens a signal it throse a swith inside the relay that opens the curent from battery to go all the way to the starter

if it cranks over-it may be an ignition system fault/ if you turn the key and nothing happens at all with a good battery-it may be a bad starter motor-the starter motor has a very small wire connection not like the big fat starter motor battery connection-it is small and comes from the ignition switch - just apply 12 volts from the battery to that connector terminal and the motor will crank-key off it will not start-turn key to ignition on- it will start, so be in park and block the wheels and do not make a mistake

Try checking the key reader it's usually a plastic ring around the key barrel. If it's dies will not read code in key to enable the car to start. Check your key is sending a code as well.

sounds like a bad connection,it wont heat up the solenoid or the starter,check your hot and negative cables from battery to starter first could be the starter itself, ggod luck

On many cars, if the battery is dead, it locks the key in the ignition. Put a battery charger on the car or replace the battery and give it a shot.

Good luck.

HI, I'm reading your problem,
Let me explain something about your car.

2005 Ford Taurus, The key on that car has Chip inside of the key and receiver on the ignition switch,
Check if the key you are trying to use is Black and has a plastic head.
If not you need a key with that characteristics.
But if you have the right key, Remenber if you had drop on the floor, or hit with something,
Because some times they come damaged, with insignificat thins.
Remenber if you left the key close to a magnets like speakers.

If nothing aply at your case, you need to call a place Aloha Smith, they have the computer to program or reprogarm your key. IF not you can't start your car.

OK.. I hope this information work for you.

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