Godholio

Today I finally finished replacing my sand-filled heater core (with a NAPA unit) and radiator (Flex-a-lite). This job involves removing the entire dash assembly, center console, and the battery tray...which means removing the TIPM and unplugging a whole lot of other connectors.

And I think I missed one during reassembly.

Symptom: Fuel gauge indicates empty. I don't remember how much is in there, but I know it's not empty. The engine cranks and cranks, but won't fire...it acts like it's out of gas. I did the gauge cluster test and the fuel gauge tests fine.

I lifted the TIPM as far as I could and checked that the connectors underneath are all plugged in completely. So's the big connector next to the battery inside the tray, and the two underneath it (can barely get to them from underneath). The two grounds on the fender next to the TIPM are tight. There's another ground point hidden under that arch where the tray bolts on top of the fender...there's nothing on that but I don't see loose cables underneath (peeking through the gap) and the paint doesn't look like it's been wrenched on.

My theory is that somewhere, there's a connector under the hood that ties the fuel pump/sender to a computer, and I left it unplugged. Does anyone have ANY idea where to find it? Or if there's something else that could cause this? The fact that the gauge reads empty but functions and the assumption that the engine isn't getting fuel tells me it's (probably) a common problem related to communication.

Edit: 2012

ronjenx

The 2012 wiring diagram shows the pump and level sensor share 2 connectors in the engine bay, along with many other systems. If either of the plugs were still disconnected, you would have many other failures.

Godholio

Whoops. 2012. It's tough to predict what wiring carried over from the 3.8 to the 3.6, and of course the FSM I've got doesn't have the diagrams.

Godholio

Which connectors?

I'll stick with this thread since we started here first.

ronjenx

C105 and C300. The 2012 diagram doesn't show connector locations like the 2008 diagram does.
In the 2008 diagram, C105 is in the area either under, or slightly behind the TIPM. C300 is forward of the TIPM, at about the same level. However, location illustrations are not very clear.

Godholio

That gives me a place to start, thanks.

Godholio

C300. It's the one on the passenger side, just next to the radiator and under the power steering reservoir. Basically right behind the right turn signal. Started RIGHT UP, thanks!

Now to figure out why my brake lights stay on, and the ABS and traction control dummy lights are lit. Even when I turn the Jeep off, the tails are lit unless I unplug the switch on the brake pedal. Aside from the Christmas tree lights (which I haven't had since replacing the OE battery with a red top) and a few short-lived cruise control switches, I haven't had any electrical gremlins until this.

ronjenx

The ABS wheel speed sensors go through C300, too.

When the brake lights stay on when the Jeep is off, what's the center high mounted light doing?
If it's on, pull fuse M1 and see what happens.

Godholio

The light is on with the others. It looks like, under normal circumstances, the pedal arm is supposed to be pressing the plunger which disengages the lights. When you press the pedal, the plunger is released and the lights turn on.

I've got a 2 or 3mm gap between the arm of the pedal and the plunger...I have no idea how that's possible, since the pedal came out as part of the instrument panel assembly. It wasn't removed, and aside from disconnecting the booster rod I didn't mess with it. I can push the plunger manually and the lights go out.

Edit: It's possible because the booster wasn't pushing the pedal out as far as usual. The lights work fine, and the dummy lights went out after driving a few feet. Durrrrrrr