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Hello
Maybe somebody can help with a fuel/fuel pump problem on my Berlingo 1999 1.8i petrol.
There is not fuel supply to the engine and I am trying to diagnose why before removing the fuel tank and pump but I cannot find a wiring diagram for my car.
I worked out that the fuel pump fuse is in the engine bay box (fuse 9??) and the fuse is good and there is power to the fuse when I crank the engine. But I don't know how to test the fuel pump relay because I cannot work out which is fuel pump cable coming out of the fusebox/relay combination.
Can somebody please help with a wiring diagram for the fuel pump or maybe somebody has another idea why the fuel is not coming to the engine or how to test the fuel pump without dismantling the tank?
Thanks in advance
Michel
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Hello
I am just reposting this. Anybody can help with a wiring diagram?
Regards
michel
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I assume that you have located the relay for the fuel pump?
It's usually called the 'Main Relay', is a little over twice as large as a normal automotive relay(because it's two relays packed into one... ) that should be bolted to the side wall of the engine room, on the same side as the battery.
A quick test is to push down and hold the accellerator pedal, then switch on the ignition. The pump should be heard engaging for a few seconds, trying to build up pressure.
If it does, you have a different issue....
If you can't hear anything, remove the relay from its socket.
I can't find a complete drawing of it, but...
this is what i found in the haynes (2010 book, there's an older one, also, that may have slightly different schematics. I don't have it here right now)
1,2 - energises the coil of one relay, and 1 goes to the alternator and 2 to Gnd(This relay activates automatically after engine starts running)
3,5 - closes thanks to 1,2 and supplies power to AC and other accessories.
The remaining pins should then be for the fuel pump...
one pin will most likely go directly to Gnd, like pin2 does.
Use a multimeter at the Resistance setting, and measure between pins 1 and 2 to find the resistance in the coil. Expect there to be a similar coil in the other half of the relay.
The remaining pins should then be for pump control.
Connect two wires directly to the coil pins, and touch them to poles on the battery for a moment to hear if it activates or not.
If it doesn't make a clicking sound, it has jammed and should be replaced.
if it DOES make a clicking sound, connect the multimeter to the pumpcontrol pins.
It should read 'infinite' or something like that until you touch the wires to the battery. Then it should drop to just about 0 immediately.
If that is also OK, you'll need to check that there's a voltage between the coil pins in the connector the relay sat in when the ignition is on.
If there isn't you have a wire break between the fuse box and the relay.
(Not a common issue)
Now, there's another possibility or two too....
Is there ONE or TWO fuel hoses connected to the High Pressure reservoir?
(Going a bit out on a limb here... I'm most familiar with the 1.4i, and th 1.8isn't covered by the Haynes book)
If there's two hoses then one is a return line, and there's a pressure regulator in the reservoir, probably as a metal cap at that end. If that regulator is busted it won't let the pressure build up and fuel won't be injected properly)
In systems with one hose the regulator is built into the pump unit.
Hopefully this should help you get started.
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