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Q: Just replaced fuel.pump and now it wont start

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I just replaced fuel.pump and when I go to start it doesnt come.on or turn over. The car is getting power all the lights come on and headlights but the fuel.pump.is not getting any power
My car has an automatic transmission.

If both the starter motor and fuel pump are not working be sure the Engine Immobilizer is not active. If you are sure the security system is off and yet power does not reach the fuel pump or the starter, there is probably a main fuse or relay that is faulty. If the starter functions but there is no power to the fuel pump, the fuel pump circuit has to be traced from the source (the battery) to the pump to find the wiring or device (fuse, relay, etc.) fault. At key on, but engine off, as you diagnose this keep in mind power will only be momentarily supplied to the pump for pressurization purposes. If you look for voltage outside that brief window, you won’t find any, and that is normal. You have an electrical problem and because the diagnostic requires the factory wiring diagram, your most efficient course will be to request a no start diagnostic. The responding certified mechanic will definitely be able to resolve this for you and if parts or components are required, the mechanic will estimate the cost.

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