I have a 1997 bmw 540i when I went to start the car nothing happend all the lights work but the starter will not engage the battery is good what is wrong ?

First, I'm not a BMW mechanic.
* How about this; https://www.amazon.com/Standard-Motor-Products-RY-777-Starter/dp/B006DX9EIW/ref=sr_1_1?ie=UTF8&qid=1530601973&sr=8-1&keywords=1997+bmw+540i+starter+relay
* be sure to plug in your car brand, model, and year for Amazon to check if it will work.
Aloha, ukeboy57

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Could be a bad battery. Should get it tested to see if it holds a good charge.

It is possible AAA worker connected the battery backwards for just a second and got a big spark. This can cause major issues, but sometimes just minor ones, such as blown fuses. Check every fuse for starters. There are also fusible links in the wiring which can be blown.

Check connection to the starter? Try it in neutral? Is there an alarm installed? Maybe active but on silent

start your car with light switch off. engaging the starter with the lights on only draws more current from battery. not a good practice.

I had a BMW 540i 2000 and that happen to me, my advice is to get the battery out of the car and recharge it. It would be advisable to have it check for malfunctioning. If it is ok, put it back on and the car will start. If not good, put a new battery, the car will start and all the lights will work in order.

Probably you could loos your radio set up and clock set up if you took too much time in the replacement of the battery, don't worry, reset the clock and the radio stations.

Yes, here is a test you can do. With the car in park or neutral and the parking brake on, short the hot terminal (one with the big red wire attached) of the starter solenoid to the smaller (ignition switch) terminal. Be careful not to let your screwdriver touch anything else, especially do not touch the big ground terminal closest to the starter motor. If the motor does not crank, the starter/solenoid is not working. If the motor cranks the engine, your ignition switch, starter fuse, or relay is bad or the start wire is open. You can further troubleshoot this by interrogating the starter relay (see tip at http://www.fixya.com/cars/r6022358-relay_check), but only some cars have a starter relay.

This is what your starter will look like. It's usually on the passanger side engine. Follow your red battery cable to the relay, then follow it from there until it reaches the starter. Make sure you remove the red cable from your battery before working on it.

go to the starter and jump the small wire connection with the big one, does the starter engage and start spinning the engine, if not the starter is bad. Hope this helps, let me know