Mercedes Benz 1989 -300e don't want to start, starter ok ,battery ok, fuel pump relay ok, when you turn the key car is dead

SOURCE: starter problems-starter works fine sometimes

I would try replacing the starter relay

SOURCE: My 2000 Mercedes Benz S500 is dead- electronic key does not

It's not that unusual for a battery to fail that soon, and the "no lights, no nothing" says that it's the battery again. Your best bet at this point is to pull the battery and take it to the point of purchase for testing. They should either replace it under warranty or charge it for you. After you replace the battery you should have the charging/electrical system checked for possible shorts or power drains.
BillB

SOURCE: mercedes vito 110cdi starter motor problems. only when the van

1.)its the alarm system cant be nuffin wrong with the starter motor i had i problem i changed the battery put a new one on and it did it so all i did was put a switch on the wire were you connect the battery very time you get in the car switch it on and strat the car in one go but evey time your job is finshed with the car switch it off but your alarm system anit gona work then
2.) but a extra battery pack the ones they use on sound systems in cars

SOURCE: Car will turn over but won't start. Through the

No noise from fuel pump when you turn over the car .First thing get voltage at fuel pump relay checked, is there 12 volt to the relay.If no, then problem is again the relay.--------- To reconfirm the problem, try other test, that is remove the relay and by pass the relay terminals with a jumper wire .Then with 12 volt external battery give power to fuel pump connector and see, if the fuel pump starts, then its clear that fuel pump relay is faulty.----------- Also other problem can be fuel pump inertia switch.If the inertia switch is faulty then also fuel pump will not start.-------- The fuel pump relay on a 1995 Ford Explorer is in the power distribution
box, in the engine compartment, driver's side near the firewall.----------
The fuel pump inertia switch is in the right front passenger area
it is below the dash but above the carpet in the right hand corner.--------
Its a push button type inertia switch.
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Fuel Pump Activation
When ignition switch is turned to START position, PCM operates fuel pump relay to provide fuel for starting engine. PCM senses engine speed and shuts off fuel pump by opening ground circuit to fuel pump relay when engine stops or engine speed drops to less than 120 RPM. When ignition switch is in ON position, EEC power relay is energized (contacts closed). Power is provided to fuel pump relay and timer in PCM. Fuel pump receives power through fuel pump relay contacts.
Inertia Fuel Shutoff (IFS) Switch
All models use an electrical interrupt switch in fuel system. During a collision or vehicle rollover, electrical contacts within inertia switch open, shutting off fuel supply to electric fuel pump. Fuel supply is interrupted even when engine is running.
A reset button is located on switch assembly. If electrical circuit trips, vehicle will not restart until switch is reset. Fuel system should be inspected before resetting switch.
IFS switch is located under instrument panel, near right side of transmission hump. ----------- If the fuel pump relay, the inertia switch and fuel pump all checked ok, and fuel pump is working with direct 12 volt source to fuel pump.Then problem relates to computer.The computer (power control module, PCM) is faulty and has to be replaced.--------- This will help.Thanks.Helpmech.

Testimonial: "Thanks. That was the best answer yet.I didn't want to hear that the PCM might need to be replaced but the car has served it's purpose through the year"

SOURCE: chevy colorado 07......fuel pump or fuel pump relay issue?

get a test lite and pull ur relay out and test it if its not lighting up then check your fuel pump