Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of September's Ride of the Month Challenge!
1 - 8 of 8 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter · #1 ·
Hi all! I fueled my 2012 wrangler unlimited yesterday while the engine was running. The gauge is still reading almost empty although it has a full tank. It only has 18500 miles on it. I am sure it is covered under warranty and i made an appt for monday to have it checked at the dealership. I would rather not spend my morning there however. I disconnected thd battery then reconnected it but still reading empty. Any suggestions?
 

·
Premium Member
Joined
·
878 Posts
Never heard of this one before. Perhaps you shouldn't fill your JKU while the engine is running?
 

·
Registered
Joined
·
1,051 Posts
bri3400 said:
Hi all! I fueled my 2012 wrangler unlimited yesterday while the engine was running. The gauge is still reading almost empty although it has a full tank. It only has 18500 miles on it. I am sure it is covered under warranty and i made an appt for monday to have it checked at the dealership. I would rather not spend my morning there however. I disconnected thd battery then reconnected it but still reading empty. Any suggestions?
Ive seen this before on another forum and am trying to find it. If i remember correctly he let it sit over night and it was corrected in the morning.
 

·
Registered
Joined
·
2,321 Posts
My bimmer is 30 minutes for an ECU reset. That's what I heard. Seems to work. Try 30 minutes at least.
 

·
Registered
Joined
·
103 Posts
Cold be a relay in the tank
 

·
Registered
Joined
·
1,251 Posts
There's a sending unit in the fuel tank. It's variable resistor connected to a float (not unlike a toilet bowl float). it will read something like 20-150 Ohms. If Jeep's system gets an erroneous value, the system defaults to displaying an empty tank. Overfillling can cause this problem. Perhaps it got stuck or broken. Also, a slight adjustment error during assembly can cause this problem. There's a chance as you burn down about 1/2 your tank it will reset. I worked with one of these systems interfacing a generic sending unit in a fuel cell for a driveline transplant. I solved it by inerting a 10 ohm resistor inline, but that's too much info.

If it doesn't fix itself at 1/2 tank you are going to the dealer. They will read the code, likely reading a malfunction and then probably drop the tank and replace the sending unit (might include a new fuel pump).

They would appreciate it if you don't take it in on a full tank.
 
1 - 8 of 8 Posts
Top