A mechanic removed one battery terminal when the engine was on. After that the engine will not start again. the car does not start. when key is turn on, no signal from starter, fuel pump.

Have you tried to turn the engine over by hand? It is curious that it died as the starter has nothing to do with the engine running. It is only used to start the engine turning over. If the motor died and will not crank with a good starter, there might just be a mechanical reason.

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 ...

What is the vehicle doing? Does it make a clicking sound when you turn it over? Or is it just dead? I assume you tried a boost.

Could be many different things. (Starter, Cables, Electrical, Computer).

Need more info on what happens when you put the key in and turn the switch.

stop the car and turn it off and don't forget to remove the key. the open the hood and find the battery. Then remove the negative battery terminal connector completely from the battery. with the battery disconnected turn on you headlamps as you would for night time driving. Wait an half an hour so all the current drains out the the electrical system. after the half hour TURN OFF THE HEADLAMPS BEFORE RECONNECTING THE BATTERY! Next reconnect the negative battery terminal connector back on the negative battery terminal don't forget to tighten it down. Put the key in the ignition turn the computer on to on BUT wait 5 seconds before actually starting the car, then start the car as normal and drive the car at least 25 miles 10 city 15 highway so the car can relearn all it functions again **Note first time start the car my be rough due that it need to relearn if it is acting rough apron start up let it idle for a bit before driving so it can calm down**

When you turn the key to the "on" position, see if the panel lights come on and try honking the horn too, if everything works it means the battery is fine.

Now, turn the key to start the engine. Does the engine just give out a click? If so, the battery terminals may be loose. Tighten the terminals leading to the battery posts with the correct tools and try turning the key once again.

U must find out why the starter is not cranking to start the engine. Have you checked battery terminals for cleanliness and lack of corrosion? Starter terminal wire good and solid? Solenoid any good? Connections? Relay issue?

Try getting a schematic so you can trace it out and find source of anomaly.

We have to assume the battery is usable, if not, anything else doesn't help. A couple of possibilities- First, get a simple, cheap device that uses a 9V battery and the car's cigarette lighter to prevent losing anti-theft codes. Once this is plugged in, remove the negative battery cable first, then the positive. CLEAN the battery connectors and terminals. Try to start the engine. If it still does the same thing, remove the negative battery cable again and follow it to its next connection and clean that point. While it is off, remove the other end of the positive cable which goes to the starter terminal and clean both points.
While under the hood, look for the cable connecting the engine block to the body of the car and clean both ends of that cable.
If the problem is still there, it can be related to one of these; the ignition switch, the starter solenoid or a corroded fuse connection. The starter is not protected by a fuse but the solenoid may be.
Good luck-

If your here just one click when you turn the key to start then i suspect you have a starter going bad.If you heard several clicks while turning the key over once then that would be a weak battery.:)

check the starter relay

(1) Remove the knee protector.
(2) Remove the relay from the underside of the relay box.
(3) Connect battery to terminal 2 and check continuity between
terminals with terminal 4 grounded.