When i turn my ignition there is only one small click, battery is new and fully charged, interior lights come on but are dimmer than normal radio doesn't turn on and once I turn on my headlights everything goes dead. , when i have it turned ignition over all the way there is only one single quiet click which is more audible while bonnet is up, it sounds central but I'm not sure it only clicks at the last step of the key turn. there is no other noise.

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Check the battery cables to make sure the hookups are not corroded. Corrosion can put a damper of the flow of electrical current and can be the entire problem. Check all terminals if they are both intact and not loose. A simple way to tell if the battery is at fault is to turn the headlights on and turn the ignition switch to start. If the lights go out, then the battery is probably at fault.
If everything looks okay, the problem may be the solenoid. The solenoid is essentially a switch that turns the starter on and off. When your car is just sitting off in the driveway, the solenoid is receiving a current from the battery, but it does not pass it on to the starter. When you flip the ignition, a small current signals the solenoid to let the current through to the starter. The starter then turns over. When you have a solenoid that is going bad, the switch can get tweaked and not let the current through correctly. Since the electrical current isn't enough to fire up the starter, the engine doesn't fire. In some cars, it just makes a click noise. Thank you for using Fixya!

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