A couple of resistors should do it to simulate the sender. 45 ohm is half tank, 90 is full tank. Remember that gage doesn't have a ground wire. Need to ground it's frame to provide ground to the meter.
Mine gauge just kind of stays wherever it feels like when the key is off. It doesn't go down to E like the newer cars when the key is off, but is pretty accurate when the key is on. You will find that it moves around a lot when you are climbing hills and accelerating quickly.
Thank you guys, I just went and got some resistors from our electrical dept. I dont have the gauge or wiring diagram with me but is there only 1 power wire for the gauge, also do I put 12v through the resistor and touch the gauge? I noticed the gauge has a little coil thing on the back of it.
Back of the gage has 2 wire. A black/pink and a tan.
Black/pink is 12 volts.
Tan is the sender lead.
Frame of the gage is ground.
The tank sender is a variable resistor that goes from 0 to 90 ohms. When the tank is empty, the sender reads 0 ohms. When it’s full it reads 90 ohms.
So with the sender wire disconnected:
Shorting the gage sender lead makes the gage read empty.
Putting a 45 ohm resistor between the gage sender lead and ground makes the gage read ½.
Putting a 90 ohm resistor between the gage sender lead and ground makes the gage read full.
Okay I just tried the test and I put power to the gauge and as soon as I grounded it, it went to E. I touched the resistor to the sending lead and ground and nothing happened, maybe I dont have the correct resistors. If I disconnect the ground and hook it to the resistor then touch the sending lead it goes to F. Tomorrow I will check to see if I got the right resistors. Thanks.
This is what Im doing, I have the gauge out of the car and Im checking it on the bench using a 12v power source. I hook up power and ground the frame, then I touch the resistor lead on the gauge with the resistor then ground the resistor. The resistors Im using are 41 and 90 ohm, they are 1/4 watt also, does that make a difference? I noticed they did get a little hot.
Well I tried again with no luck, Im going to take it to work and have a electrical guy check it out. I know the gauge has to work because when you short the sending circut it goes to E. I will post back in the morning.
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