Fuel gauge testing ( pegged)

[mouserider]

Hey forum, trying to find issue with my fuel gauge not working (always pegged)

so, it started to peg once in a while and now it just always pegged.

So, tested the voltage in regulator, 12 in, out pulsing from 0 to 6, like (0, 3, 6,0,6,3) i assume this is normal, also my other gauges (coolant, oil pressure) works fine and as far as i know they all work via same regulator.

Next i tested the gauge both leads (one of the leads show pulsing 0-6, another lead shows pulsing 0-2v.

is this normal? i thought that fuel gauge should show the same voltage both in and out?

Thanks

Charger 1971 SE, 383

 

[davek]

It helps to know what your working on.

 

[davek]

Testing gas gauge. - Moparchat - Home of MOPAR enthusiasts worldwide!

Can you guys tell me how to make sure my gas gauge is burnt out, before I go through the touble of pulling it out? All the other gauge's work fine Im

www.moparchat.com

 

[mouserider]

It helps to know what your working on.

sorry, edited first post

 

[dadsbee]

Sender wire is grounded out some where

 

[Nxcoupe]

Hey forum, trying to find issue with my fuel gauge not working (always pegged)

so, it started to peg once in a while and now it just always pegged.

So, tested the voltage in regulator, 12 in, out pulsing from 0 to 6, like (0, 3, 6,0,6,3) i assume this is normal, also my other gauges (coolant, oil pressure) works fine and as far as i know they all work via same regulator.

Next i tested the gauge both leads (one of the leads show pulsing 0-6, another lead shows pulsing 0-2v.

is this normal? i thought that fuel gauge should show the same voltage both in and out?

Thanks

Charger 1971 SE, 383

Disconnect from sender in tank. Just unplug it. Turn key on, if gauge goes to empty, sender has failed. If it stays pegged, wire is grounded somewhere.

 

[mouserider]

Disconnect from sender in tank. Just unplug it. Turn key on, if gauge goes to empty, sender has failed. If it stays pegged, wire is grounded somewhere.

Thanks, done. Disconnected sender - gauge reads zero. I also checked the resistance on the sender - 17, feels about right, it was almost full. Should I just go and replace sender or there are other thing I can do? Sender is literally brand new

 

[Nxcoupe]

Thanks, done. Disconnected sender - gauge reads zero. I also checked the resistance on the sender - 17, feels about right, it was almost full. Should I just go and replace sender or there are other thing I can do? Sender is literally brand new

Only way to test it is to remove it and run it through its range while watching an ohmeter. 3 to 4 ohms should be full, and 60 to 70 should be empty.

 

[451Mopar]

Disconnect the fuel level sensor at the tank and the gauge should show empty.
If it shows full, the sensor wire might be shorted? If still showing full, disconnect sending unit wire at gauge and re-check. With nothing connected the gauge should show empty unless the gauge is bad.

If the gauge went to empty on the first step after disconnecting from the sending unit, the the sending unit is likely shorted or stuck.

A quick gauge check would be to connect a 20-Ohm resistor to the sending unit wire and the other side to ground. The gauges should show 1/2 tank.

 

[Nacho-RT74]

It helps to know what your working on.

Mmmmmmm, actually it makes no difference, since all mopars gauges works the same

 

[Nacho-RT74]

Thanks, done. Disconnected sender - gauge reads zero. I also checked the resistance on the sender - 17, feels about right, it was almost full. Should I just go and replace sender or there are other thing I can do? Sender is literally brand new

If you have patiente, knownledge and skills, could be fixed depending on what it took to the failure. First step is remove it from tank. Being replaced or fixed, this step is the same on both stages.