07 F150 5.4L 2WD Supercrew low fuel/tank full/runs good
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07 F150 5.4L 2WD Supercrew low fuel/tank full/runs good
2007 F150 Lariat Supercrew 2wD 5.4L Auto
Low fuel on digital readout....tank full of gas, runs good.
Anyone tell me where to start?
Signed
Dumbass
Low fuel on digital readout....tank full of gas, runs good.
Anyone tell me where to start?
Signed
Dumbass
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Joined: Jul 2004
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From: Easton, Pa.
The tank level signal is a vairable resistance signal supplied to the dash where it is converted to a digital signal then back to analogue that drives the >> analogue dash gauge.
The dash is all electronic for other functions so the conversions are done to make the tank level available through the same system as the other functions..
Could be anywhere between the end points.
Pump level control, Tank plug, wiring, dash function failure, gauge failure.
You may have a dash test mode that would give you the tank level as an Octal number. If yes, the dash electroncs output may be in fault to the gauge.
This is part of dagnostics.
Good luck.
The dash is all electronic for other functions so the conversions are done to make the tank level available through the same system as the other functions..
Could be anywhere between the end points.
Pump level control, Tank plug, wiring, dash function failure, gauge failure.
You may have a dash test mode that would give you the tank level as an Octal number. If yes, the dash electroncs output may be in fault to the gauge.
This is part of dagnostics.
Good luck.
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Yeah. I sorta knew all of that, since I'm an old Naval Aviation Electronics Technician.
I just kinda sorta thought, you know, that someone would help an idiot like me know what points to check and how to do the checks and where to do the checks. Dummies like me know nothing about trucks.
wow
I just kinda sorta thought, you know, that someone would help an idiot like me know what points to check and how to do the checks and where to do the checks. Dummies like me know nothing about trucks.
wow
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I have a full tank. I walked to truck after some tv and stereo repairs at my shop, and when I cranked the truck, noticed low fuel readout and E on fuel gauge. I thot my gas been stolen. I poured 5 gal., it overflowed, so it's full.
. I grounded the black/orange stripe to be sure the sending unit, components had good ground. It still pegs to left under the E. My next step (I guess) is to ground the white/yellow stripe going to sending unit to see if gauge goes to F. I'm assuming that would tell me whether the gauge is good or not.
. I have a dual trace scope at my tv shop, and I think the gauge uses a PWM signal from the gauge assembly, then back from sending unit, instead of DC ? You can probably tell I'm an idiot when it comes to automotive, but I got ripped off hundreds of dollars at the local Ford dealership, so I feel like I have to do this, or bend over again.
. I appreciate the reply. I feel like a vagrant asking for a dollar, but this one time in my life, I'm going to ask for help!
. Thanks
BTW....I thought I would check resistance from ground to the white/yellow stripe (from sending unit) and see if I get a low resistance on the meter. My vague understanding is low ohms (10-15) is full, and high(er), 130-150 ohms is empty.
Thanks ahead
. I grounded the black/orange stripe to be sure the sending unit, components had good ground. It still pegs to left under the E. My next step (I guess) is to ground the white/yellow stripe going to sending unit to see if gauge goes to F. I'm assuming that would tell me whether the gauge is good or not.
. I have a dual trace scope at my tv shop, and I think the gauge uses a PWM signal from the gauge assembly, then back from sending unit, instead of DC ? You can probably tell I'm an idiot when it comes to automotive, but I got ripped off hundreds of dollars at the local Ford dealership, so I feel like I have to do this, or bend over again.
. I appreciate the reply. I feel like a vagrant asking for a dollar, but this one time in my life, I'm going to ask for help!
. Thanks
BTW....I thought I would check resistance from ground to the white/yellow stripe (from sending unit) and see if I get a low resistance on the meter. My vague understanding is low ohms (10-15) is full, and high(er), 130-150 ohms is empty.
Thanks ahead
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Road block...
Roadblock is this gadget. The Y/W , and the Bk/Or wires that leaves the potentiometer (float) go into this IL2U-14A069-AB pcb. I get 15 ohms on full and 130 ohms on empty, as far as the level of fuel. I thought it may be a "slosh" switch that was referenced in other forums, but there is nothing to indicate anything like that. After a few minutes on the sander, i dug this out of the plastic shell. If anyone knows where i can find a diagram to troubleshoot?