Car wont start Makes clicking sound Battery Light steady red color Need to add oil. What is wrong and how can I fix it?

The "mechanic" made a wrong connection of the wiring that fixed itself.

Most likely starter motor sticking

Is your car still under warranty? I would contact the dealer. This could be several things ... something as simple as a bad alternator could cause the battery to drain which in turn could cause the on board computer to cause weird things to happen ... ie oil light. Trying to restart a car with a low battery wil usually give you this clicking sound. This can easily be checked with a volt meter. It should be12 - 14 volts. It should never fall below 10 volts ...Or it could be something as major as a cracked block letting the water and oil mix in turn causing the car to over heat.

Is the theft light on steady? Is there power to the starter on the small wire with the key in the crank position?

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sounds like a wire or ground wire is contacting at a pinch point, and grounding out the system. first have the battery voltage checked, it should be no less than 12v, and no more than 14.5v, during cranking it can drop to 8.5v but no less. any new parts installed, such as a ignition switch???/
may need to be reprogramed to match the computer, or just fix a bad connection.

sounds like a bad battery. have you tried to jump it? if it starts, go to a chain auto store like pepboys or auto zone they will check it for free. it might also be the starter. if you can access the starter, have someone tap on it with a broom stick or something similar while you try to start it. the starter is located on the rear part of the engine where the trans meets the engine. a cylindrical device with red colored, large wires connected to the back of it.

Sounds like corroded battery terminals

Sounds like a bad starter solenoid, usually cheapest and easiest to replace the starter and solenoid as a unit. It is always best to check for power between the solenoid and the starter with a test light, if the solenoid clicks but the test light doesn't light up you have found the problem in the solenoid.

Sounds like possiblity of the oil pump being bad, and is setting off other sensors on your car.

Hatterasnc,

You're alternator has gone bad and the vehicle was running on battery power. The "clicking" sound is your now dead battery that does not have enough power to turn over the starter. You might also want to check your power steering pump for leak. This is a know problem with early LS400s and will most likey be the cause of the alternator failure. I just dropped $1050.00 to fix the very same promblems you have.