Crank, no start.

[Don Hall]

Check lite b4 u order. If its blinking, could b a whole new series of prob. Im dealing with this now re pats system. Not the key, not transceiver, not module. Then wat? Antitheft lol. Who wants to steal my 99 expedition. Cranks, and no start. Keep us posted pls

The Expedition is running just fine now, so I would not expect to see a blinking light. I have extra keys in the vehicle just in case the key chip and computer ignored each other.

 

[roadrunnerkitten]

The Expedition is running just fine now, so I would not expect to see a blinking light. I have extra keys in the vehicle just in case the key chip and computer ignored each other.

Nice. I guess my computer n key r gettin a divorce after ignoring each other lol.


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[Don Hall]

......... Keep us posted pls...

Will certainly post results (junction box ordered today).

 

[1955moose]

Be sure Don you get the correct part # box, as most are not swappable. It sounds like your relay is breaking connection, and then connecting. Most if not all 2003-06 seem to have this problem, most are more severe than yours, your actually one of the luckier ones.

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[Don Hall]

Be sure Don you get the correct part # box, as most are not swappable. It sounds like your relay is breaking connection, and then connecting. Most if not all 2003-06 seem to have this problem, most are more severe than yours, your actually one of the luckier ones.

Thanks for the advice, 1955 moose. Ordering is straight forward (https://www.autopartscheaper.com/products/2004-expedition-navigator-fuse-junction-box).
Thanks to stamp11127, this forum provided a viable solution.

 

[stamp11127]

I hope the junction box is the problem but keep in mind if your mechanic hasn't bypassed the fuel pump relay to test the fuel pump, you may be swapping that out also.

FYI relays do not reset themselves. Think of them as a big heavy duty switch connected to your Itty bitty remote push button switch. A small amount of electricity is controlling a larger amount. Remember the points and condenser days, with the points pitting after a while? Same thing can happen to the contacts in a relay.

 

[Don Hall]

I hope the junction box is the problem but keep in mind if your mechanic hasn't bypassed the fuel pump relay to test the fuel pump, you may be swapping that out also.

FYI relays do not reset themselves. Think of them as a big heavy duty switch connected to your Itty bitty remote push button switch. A small amount of electricity is controlling a larger amount. Remember the points and condenser days, with the points pitting after a while? Same thing can happen to the contacts in a relay.

OK, stamp11127, I need a tutorial. If relays do not reset themselves, what component would reset allowing my vehicle to start after a few minutes? I'm aware the inertia switch must be manually reset. Would/could a failed fuel pump reset allowing a restart? I don't think anything fuel related can reset itself.

Can you test a working fuel pump by bypassing the pump relay? (I realize an idiot can ask more questions than a genius can answer).

 

[stamp11127]

it isn't a case of "resetting" more to the tune on making enough contact to "close" the circuit and allow current flow.

This will give you an idea of what can happen at the contacts. The pitting is on the darker discs and acts as a resistor. That in turn drops the voltage & current to the load.
https://www.google.com/search?q=pit...AUICigB&biw=1344&bih=734#imgrc=V-qID6b3UFcoRM:

This is another failure that can occur in the junction box on that circuit.

https://www.google.com/search?rlz=1.....0.0.0....0.S3O_F4WMmgw#imgrc=tG5KbXZYPYi00M:

The bright silver lines are the "wires" on the printed circuit board (pcb) and are called traces. Notice the width of the trace will vary, just like the diameter of wiring in the vehicle. More area, larger diameter wire, means it can handle more current.

I would venture a guess the newer updated box has wider traces on the fuel pump circuit.

Yes to jumping the relay to test the fuel pump.

 

[Don Hall]

......it isn't a case of "resetting" more to the tune on making enough contact to "close" the circuit and allow current flow.

Great response, stamp11127. Your assessment coincides with the vendor's comment: "Unfortunately, at one time or another every 2004 Expedition experiences this problem. The issue arises inside the fuse box where the circuit board meets the relay. The contacts heat up where these two meet and eventually fail due to the connection melting."

If my problem is due to a melted connection, then the updated circuit board (conjunction box) should solve the problem. I will contact the vendor Monday, and see what I can learn.

Thanks a million for your time and intellect.

 

[Don Hall]

If it was a key issue the theft light would blink rapidly. If it isn't the usual problem is the fuel pump relay in the smart junction box.

OK, stamp11127, back to your first response to my dilemma (post #2, and a query from roadrunnerkitten post #20)....... "blinking light". I have not confirmed if my anti-theft light blinks during CRANK, NO START.

I need to confirm a blinking light, or not. I have searched, but have not learned to my satisfaction if the anti-theft function resets over time. If so, that would account for
the restart after some (30?) minutes. My problem may not be fuel related at all.....(I'm not the sharpest tool in the box). I may just need to change keys.

Antitheft reset: According to the owner manual there is no delay to insert a new key:

"Automatic disarming
Switching the ignition to the 3 (ON) position with a coded key disarms the vehicle."



Again, I have not found anything fuel related that resets itself.

I have changed ignition keys, and now carry 3 keys (2 with fobs) in the vehicle.
We shall see if the CRANK, NO START problem is solved.

Order for updated junction box cancelled.