turn the key and nothing happens
If you have had your battery load tested, not just somebody putting a mult-meter on it and it shows 12- 13 Volts..that is not a true test. But going under the assumption that it was load tested, and is good, next is starter, cables or security. There should be a small red LED that blinks when car is off and key out. If you put your key in and the red light continues to blink it's an anti-theft problem. You don't even have to turn the key, when inserted in ignition switch the light should go out. That means the ECU has recognized your key. If it keeps blinking there is your problem. If it goes out, make sure cables are tight on battery, and you can take a long-shot and whack the starter with a RUBBER mallet. Please let us know what happens.
Do you have any power at all? When you turn key to 'run' do the dash warning lights light up?
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