P0462 Code

[professor229]

From the top....

Restoring and almost done with a 2004 Ford Ranger XL with 107,000 miles. Replaced the badly dented pickup box with a Texas used box after restoring. While the old box was off I somewhat cleaned up the frame to a basic degree. Installed the new box. Life is good. I have driven it for a year now and about a month ago, the "check engine" light came on. I pulled the positive cable off overnight, hooked it up the next day and the light was of course, off. Drove the Ranger for a good month with no check engine light returning. A couple days ago, the check engine light popped on. Thought about it... and the first time the light came on was after I put in $20 worth of gas. Then I shut off the light, and this time, I again put in only $20 of gas and surprise, the check engine light came on again. My son brought his code reader and we just plugged it in and I had told him I bet it has something to do with the fuel system. Sure enough P0462....... I just finished reading all about it and wonder if anyone else has fixed this... Do I have to remove the box to get to the tank or can this be done by my mechanic on a lift? What else should I consider? Thanks for your help.....

 

[RonD]

For those who don't have the whole code list memorized, lol

P0462 Fuel Level Sensor Circuit Low Input

So is your gas gauge working?
If not then yes, most likely a wire at the tank got unhooked, but should have been a "Low Fuel" Light on the dash

There is a Yellow/white wire and a Black/white wire at the top of the gas tank for the sender hookup
The yellow wire runs to the computer and to the instrument cluster, if gauge is working then the splice of the yellow wire to the computer is bad

The black/white wire is the ground for the sender so if it was bad then neither the gauge or computer would get a good fuel level signal

Lower right of diagram shows the Sender in the tank and the two wires

 

[professor229]

From the top....

Restoring and almost done with a 2004 Ford Ranger XL with 107,000 miles. Replaced the badly dented pickup box with a Texas used box after restoring. While the old box was off I somewhat cleaned up the frame to a basic degree. Installed the new box. Life is good. I have driven it for a year now and about a month ago, the "check engine" light came on. I pulled the positive cable off overnight, hooked it up the next day and the light was of course, off. Drove the Ranger for a good month with no check engine light returning. A couple days ago, the check engine light popped on. Thought about it... and the first time the light came on was after I put in $20 worth of gas. Then I shut off the light, and this time, I again put in only $20 of gas and surprise, the check engine light came on again. My son brought his code reader and we just plugged it in and I had told him I bet it has something to do with the fuel system. Sure enough P0462....... I just finished reading all about it and wonder if anyone else has fixed this... Do I have to remove the box to get to the tank or can this be done by my mechanic on a lift? What else should I consider? Thanks for your help.....

For those who don't have the whole code list memorized, lol

P0462 Fuel Level Sensor Circuit Low Input

So is your gas gauge working?
If not then yes, most likely a wire at the tank got unhooked, but should have been a "Low Fuel" Light on the dash

There is a Yellow/white wire and a Black/white wire at the top of the gas tank for the sender hookup
The yellow wire runs to the computer and to the instrument cluster, if gauge is working then the splice of the yellow wire to the computer is bad

The black/white wire is the ground for the sender so if it was bad then neither the gauge or computer would get a good fuel level signal

Lower right of diagram shows the Sender in the tank and the two wires

Thanks Ron..... And yes... I noticed something "different" about the gas gauge in the last year. When I got home I would glance at it and it would say something like 3/4 full.... The next morning, on start, it would say something like 1/2 full..... then as the truck warmed up on the way to the lake, the gauge would slowly correct itself to the 3/4 level....

And just some other thoughts.... I am old... I have done my time..... in my youth I would have gone after this. Today, I am going to do nothing. The gas gauge still works but I will only keep 1/4 of a tank of gas in it and drive it with the check engine light on. If the gauge fails, then I will pay my local mechanic to "fix it" and may consult with him in the next few weeks about this anyway.

This is not my first experience with this. I replaced the gas tank in one of my project cars many years ago now and had to install a new universal sending unit after running out of gas luckily near a gas station out in the sticks. It still does not register right but when the gauge gets to half a tank, it's time to fill up the tank.

My very first car did not have a working gauge... so I had a notepad, and wrote down the odometer reading each time I filled up the tank. I was a very struggling college student at the time. I did the math and filled up the tank every 200 miles. Since I worked at a gas station, this was NOT a big deal.

I am sure the mechanic will know this answer, but can you see those two wires on the gas tank without removing the tank? In other words, put it on a hoist and check? or do you remove the gas tank? I have seen some truck beds with a square foot of their bed floor replaced with a hinged plate for access to the top of the gas tank....

And also, the sender unit for this on Rock Auto is about $100.... is that right? Other options? And I suspect two hours of labor to remove the tank and replace? So the estimates were about $300..... or am I dreaming?

Again... thanks for the information.....

 

[RonD]

To access fuel pump assembly or the wires on the top of the tank at home you lift the bed off or tilt it up in the front, just 6 bed bolts and 3 screws for filler

In a shop with a lift and transmission jack they can lower the gas tank while unhooking the hoses and wires, not recommended at home because getting it out is not a big deal but getting back in IS A BIG DEAL, lol

The former, bed lift method, would be preferred in this situation since you can view the wires plugged in at the top of the tank as they are sitting now
And since the bed was just replaced the bed bolts will not be rusted or crusted up, so easy to remove

Since the gauge seems to work and no "Low Fuel Level" light my guess is the problem is not at the gas tank but in the wire that splits off to computer or the computer connection of that wire

Computer has these 5 codes to chose from
P0460 Fuel Level Sensor Circuit Malfunction
P0461 Fuel Level Sensor Circuit Range/Performance
P0462 Fuel Level Sensor Circuit Low Input
P0463 Fuel Level Sensor Circuit High Input
P0464 Fuel Level Sensor Circuit Intermittent

P0460 would be a bad sender or broken wire, basically No Connection
P0464 as well

P0462 means there is a connection but its reading lower than the lowest "in range" voltage it should see, which can be a corroded connection at the splice or at the computers pin

You could unplug the 104 pin connector from computer and inspect the slots and pins for signs of water intrusion, clean it if found, then plug it back in, the simple act of unplugging and plugging back in ANY connector cleans the slots and pins
Clear the code and start driving again and see if it comes back

As said this code can not effect vehicle operation, so not an urgent fix code


Ford gas gauges often settle at a spot with key off, they don't hold at previous driving level, that would run down the battery
So with key on you should see the correct fuel level in 5 to 10 seconds, the delay is from an anti-slosh circuit which prevents instant levels all the time with key on, if it didn't have this the gauge would go up and down every time you went around a corner and the gas "sloshed" around in the tank

 

[professor229]

Lots to think about and thanks so much for all the options.... Some random thoughts... I will need to look to see where that 104 connector is located.... and see if it is corroded... there is a strong possibility of that because on the firewall is the resistor for the fan speed.... when I bought the Ranger it was either on high speed or off... I tore into it and tried to separate the two plugs... they were so rusted they were fused together; I still have it ... a trophy.... I even put it in the vise and tried to pull it apart... no go.. so there is a history of rust on this Ranger..... Next, I found a seven foot box from Texas and restored it and it replaced a bashed in box... Got it set on the frame with the help of a friend... and then installed the bolts after cleaning them up, almost like new... and like always, restoration 101... I put anti-seize on all the threads.... so I have no doubt that I can loosen these easily and lift up the front of the box to get access to the tank if I need to replace the sending unit.... but I will check for damaged wires and that 104 first... The Ranger basically pulls my small boat trailer five miles and back to the lake... so running out of gas is pretty much hard to do... and the gas gauge still does work... One other thing... the last two times I have fueled up the Ranger, I only put in $20 worth because of the gas prices here... so I only have about half to 3/4 of a tank... The check engine light does NOT come on immediately... it comes on the next day usually.... Now, if I shut that light off by disconnecting the battery... the check engine light does NOT come back on for a couple weeks until I refuel it again... then the next day, the light will come on... The plan next time is to fill the tank and see what happens... I am in no hurry to do any of this... PS.. I have a topper on this box.... so it makes sense to remove the front bed bolts and loosen the back ones and slide a 2x4 under it.... to hold it up.... Lots of ideas which I thank you for.... send some ambition...... LOL

 

[txsleds]

@professor229 I too am old. Check and clean the ground strap on the frame from the fuel sending unit.
Might be a good opportunity for you to supervise someone wanting to learn. Think High School or Junior College Shop Teachers looking for a project.
Local universities usually have an Automotive Club. This video may help you decide.

 

[professor229]

Will check the ground strap first... then perhaps talk to my mechanic... he might know some tricks that I don't know....