Fuel Level sender circuit diagram
rkvons
11-20-2013, 01:21 PM
I have a 1998 Trans Sport Montana. Anyone willing to provide the circuit diagram of the Fuel Level sender/gauge circuit? I replaced my fuel level sender and my gauge occasionally goes to full still. Thanks,
Tech II
11-20-2013, 04:47 PM
Then you should check the harness to the fuel tank......look under the vehicle, driver's side, approx. where the back edge of the front seat is.....you will see a harness or harnesses coming out of the floor...these harnesses feed the tank, rear ABS, etc.....
When you disconnect the harness and look at the end of the harness and the connector it plugs into, you will probably find "green" corrosion, which can get bad enough to increase resistance to a point of making the sender think it is full.....sometimes it can be cleaned, sometimes the connectors have to be replaced....depending on which circuit is affected, it can cause a no start(fuel pump circuit), fuel gauge problem, ABS light coming on, etc.
When you disconnect the harness and look at the end of the harness and the connector it plugs into, you will probably find "green" corrosion, which can get bad enough to increase resistance to a point of making the sender think it is full.....sometimes it can be cleaned, sometimes the connectors have to be replaced....depending on which circuit is affected, it can cause a no start(fuel pump circuit), fuel gauge problem, ABS light coming on, etc.
rkvons
11-21-2013, 01:09 PM
Then you should check the harness to the fuel tank......look under the vehicle, driver's side, approx. where the back edge of the front seat is.....you will see a harness or harnesses coming out of the floor...these harnesses feed the tank, rear ABS, etc.....
When you disconnect the harness and look at the end of the harness and the connector it plugs into, you will probably find "green" corrosion, which can get bad enough to increase resistance to a point of making the sender think it is full.....sometimes it can be cleaned, sometimes the connectors have to be replaced....depending on which circuit is affected, it can cause a no start(fuel pump circuit), fuel gauge problem, ABS light coming on, etc.
My first attempt at this was to look at that connector. I only looked at the underside. I did not look at it from above the floor under the carpet. Anyways, I did not see anything unusual. I will look again. Thanks.
When you disconnect the harness and look at the end of the harness and the connector it plugs into, you will probably find "green" corrosion, which can get bad enough to increase resistance to a point of making the sender think it is full.....sometimes it can be cleaned, sometimes the connectors have to be replaced....depending on which circuit is affected, it can cause a no start(fuel pump circuit), fuel gauge problem, ABS light coming on, etc.
My first attempt at this was to look at that connector. I only looked at the underside. I did not look at it from above the floor under the carpet. Anyways, I did not see anything unusual. I will look again. Thanks.
tmartin000
12-11-2013, 08:19 PM
Tech II
12-12-2013, 10:09 AM
It doesn't even have to have corrosion.....you can have a female connector that is too loose, causing arcing which will increase resistance....
The same thing could happen at the connector at the tank....make sure all female connections are clean and tight...
The same thing could happen at the connector at the tank....make sure all female connections are clean and tight...
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