I replaced my battery in the Mercedes Benz and it's
been a week and the car has powers everything on
it work but engine doesn't start what can it be
wiring, starter, fuel or ignition, hard to say without doing some tests.
Check the battery connections to the battery and to the starter. If you had a dead battery, it sounds like you may of had a cable come lose and short out the battery and drain it dead. You may have a stater silenced gone bad and the battery itself is fine. Do you have to program the new battery to the car's computer? That may be the issue also. Some cars computer system has to have the battery reprogramed to it if it exchanged or even disconnected.
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