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Q: Full power but no turn over when key is turned

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My car is exhibiting a problem with starting. When I turn the key there is full power, but it will not turn over at all. There is a new alternator in my car and I have checked the battery. I’m certain that the problem is not the starter. I have read that sometimes a problem like this can be caused by the ignition switch, or crankshaft position sensor might be bad. It is strange to have full power, but no turn over. What is causing this and how can a solution be found?

Hey there, I believe you are correct. The most likely cause of this issue you are having would be the ignition switch. The ignition switch is responsible for sending power from the battery to the starter when you turn the key. Many times, the ignition switch can only partially fail which will allow some functions to still work.

I would recommend having your ignition switch tested using the manufacturer’s recommended procedure by a qualified technician such as one from YourMechanic. If the ignition switch is faulty, the only way to get the vehicle to start would be to replace the ignition switch.

I think that the crankshaft position sensor is a possibility but not a very likely cause because many vehicles can still start and run with a bad crankshaft position sensor. Also, a bad crankshaft position sensor will not affect the starters ability to crank.

If the vehicle is at your home or office, you would normally have to tow it to a shop to get the repair. If you have the turning over problem inspected by YourMechanic, you can save the tow cost and have the issue repaired on site.

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