fuel gauge light

cachethunder

Registered User
Hi everyone, yesterday i change my old fuel pump, for a new 255 lph ebay pump, work excelent. but i have a problem after install, the light of check gauges doesnt turn on and the vmm monitor stay in normal ( green ), but the needle gauge is ok, it measures correctly, i know because it calculate as much as gasoline remained . Do you know what are wrong, :confused: :mad: please help me
 
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Hi everyone, yesterday i change my old fuel pump, for a new 255 lph ebay pump, work excelent. but i have a problem after install, the light of check gauges doesnt turn on and the vmm monitor stay in normal ( green ), but the needle gauge is ok, it measures correctly, i know because it calculate as much as gasoline remained . Do you know what are wrong, :confused: :mad: please help me

sorry, but i dont write all the words the first time on my first message,but is edit now, and please somebody help me
 
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I always thought that the "check gauge" light and the VMM use the same signal as the fuel level gauge. I'll have to look it up when I get home. :eek:
 
vmm and check gauge trigger at different levels. Best I can remember is that there are multiple wires going to the sending unit. Since the fuel level only needs 1, then I'm betting they used 1 for level guage, possibly one for check gauge light and the other for the vmm and 1 possibly for ground. I would think you have a bad wire connection somewhere in between the harnes and the sender.
 
vmm and check gauge trigger at different levels. Best I can remember is that there are multiple wires going to the sending unit. Since the fuel level only needs 1, then I'm betting they used 1 for level guage, possibly one for check gauge light and the other for the vmm and 1 possibly for ground. I would think you have a bad wire connection somewhere in between the harnes and the sender.

The fuel pump is in there too ;)

The two warnings maybe be on one wire while the gauge is separate. According to his problem, that's how it should be.
 
I just looked at the install on www.mn12performance.com, good pictures. It looks like sender has 3 wires, 2 for the fuel pump and 1 for the sender. Therefore the sense must be triggered on amount of resistance in the sender. So all 3 are in the same wire. It must be triggered elsewhere, have to look at the wiring diagrams now..
 
IF I remember rightly, the VMM should light up when the tank is at 1/8 according to the gauge. The light will light up when it gets down almost to the E which indicates roughly 2 gallons left.

All of those are fed on the same wire from the tank.
 
The "Check Gages" light is triggered when the voltage at the fuel gauge drops below a certain amount. So all the triggering happens right at the gauge cluster, I am pretty sure. I think the output wire from the fuel sender is split and feeds the VMM as well. So if the VMM warning isn't working, it's probably a problem with the VMM.
 
This is more along the lines of what I would expect...

So, either the sending unit is messed up somehow - wrong fuel pump strainer perhaps? - everything is working fine, or something is messed up in the VMM/cluster wiring.

My guess is that the strainer is a Mustang version! :D
 
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