Bmw 118i not starting

SOURCE: 1993 540i bmw .i tried starting the car but it

try to change your crancshaft sensor

SOURCE: how do I reset the computer on my 118i bmw if I change the battery

Instructions

Turn your ignition key to the accessory position when the lights and radio come on (before starting the car).

Press and hold the "Trip" button on the instrument panel until the red light comes on.

Press the "Trip" button a second time and hold until "Reset" appears.

Press the "Trip" button a third time. The computer is now reset

SOURCE: BMW 318I 1988

Sounds like you have an electrical problem. I think it would be an idea to let an expert have a look at it even if they only diagnose the problem and you conduct the repair yourself.

SOURCE: our BMW 318 wont start

try looking at the ignition lock/starter relay.as a fist step.