2003 monte carla will not start i put a new starter on car was working will not start now they say its the starter relay

Did you check fuses and relays first? Diagnose first, then repair. A new motor comes after you connect 12 volts to the old one and see if it works.

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Fuse Box Diagram Chevrolet Monte Carlo (2000-2005)

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2000, 2001, 2002, 2003 - Here you will find fuse box diagrams of Chevrolet Monte Carlo 2000, 2001, 2002, 2003, 2004 and 2005, get information about the ...

Question edited for clarity.

Check the relay.

https://www.google.com/search?q=2003+BMW+X5+fuel+pump+relay

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bad starter hold key on and have someone hold test light on small wire on starter or tap on starter with hammer when it acts up to verify 2 person job

need to narrow down to electrical or fuel management --when no start is fuel pump working ---has the ignition system been tested or starter when no start

maybe starter relay?

should be in the engine compartment on drivers side/most of your main engine relays are there/should be a fuse box...

please be more specific --- will not start after ???

not sure what you mean this car doesn't have an (antitheft relay) it has a BCM that receives resistance data from ignition switch and when the data matches programming then car will start. if the data is changed or not reading then the car will not start and security light will flash BCM will shut down starter and fuel delivery. if the security light flashes when you attempt to start the car. the security sensor in the ignition switch will need to be replaced and programmed to the BCM. this is very common problem to these cars.

the flasher or blinker is defective or loose.

resistor.............tell the mehanic