I don't have a ESOF problem, 4 wheel drive works just fine on my 06 F350. The problem is with the bulb behind the 2WD/4X4 High/4X4 Low that lights up when the headlights are on burnt out. I've taken the bulb out and took it to the dealer. They cannot find the bulb and want you to buy the whole new switch assembly $50.00. Part 5C3Z-14B166-AA. But the bulb comes out. I just took a small screw drive put in the "X" on the back turned it 1/4 turn and socket and bulb comes out. So why not just go buy a new bulb, that's the problem take a look at the pictures attached. It's not just a normal bulb. The green rubber piece comes off but there's no part number on the bulb. Plus it needs the long leads on it in order to wrap around the blue plastic piece. Does anyone know where I might be able to get this part short of going to Radio Shack and looking.

Pictures are here.
MobileMe Gallery

 

I replaced mine with a bulb that I found, but later replaced that bulb with an LED which is much better.

Here's some info I put together about this...

2004 F250 Dash Light Bulbs

 

Thanks let me look and I'll post any further questions if I any.

Thanks again.

 

Looks like some time after 2004 they may have changed the contact points as my contacts are the blue arrow in your pictures.

 

That's cool.... that actually gives you more options, I think...

Here's another writeup I did for my dash lights that shows some of the LEDs I used.

2004 F250 LED Dash Lighting

You might be able to use the one below directly. You could plug it in and try it and if its not bright enough, you can take it apart and do like I did with mine (use the original gray housing)

 

Found these also. About 1/2 way down the page. Type B Tall (T4)

Autolumination Instrument Panel Light Bulbs & Lamps)

 

Just ordered 2 from Autolumination. Hopefully they work and I don't have to do anything special if not I'll figure out how to adapt them to work.

Thanks for the help. I've Bookmarked your site for future reference.

 

Good find on that site! I haven't seen the tall ones yet.

Keep us posted on how these work. If they do work, and you don't mind, I'll add your findings to my writeup (credit to you, of course)

 

Sure thing..

 

Heck, I just ordered a new switch and it came in without the blue/green lens condom.

 

Just got the new LED from Autolumination and it works like a charm once I got the polarity correct. If you do get them take a sharpie and make a mark on side of the base. That way if the polarity is incorrect you have reference point as to which way it was installed.

But other than the it works. It's slightly a different green tint as it's LED and not the traditional bulb with a green rubber condom over it. But all in all if you can live with that it's much cheaper than replacing a $50.00 switch for a $4.00 part.

I'd use Autolumination again also. Their site looks a little risky, but I paid through paypal so I had someone to help get the money back if I never received the product. But they're good, order on the night of the 7, got shipping notice on the 9th and got the product on the 12th.

 

That's great news!

If you can post up exactly which bulb you used, I'll add it to my tech article, as mentioned above. Was it just the "Type B Tall (T4)" in green?

Good job!

 

Yep, That's what it was.. about half way down the page.

Neo - Wedge Tall LED Instrument Panel Bulbs
Type B Tall (T4)/Neo Wedge Instrument Panel Bulbs/10mm= 3/8"
http://superlumination.com/images/au...ll_dims_wm.jpg

 

Ok... I just added that info to both of my articles that involve this bulb...

Thanks again to james734 for finding the direct replacement LED bulb! How bout some reps for the man?

2004 F250 LED Dash Lighting

2004 F250 Dash Light Bulbs

 

Hey Guys- I think there may be a couple different versions of the ESOF switch. Some have the bulb contacts on one side of the circuit board. Some have it on the other ? I just ordered 2 green LED's. Wouldnt work because my contacts are on the opposite side of bulb socket. Tried to remove LED from new socket to transplant into old... But destroyed it in the process. It was all glued / sealed on the inside. SO I uncoiled the wires of my second LED and passed wires through socket hole and soldered to circuit board traces. Works ! However a little too green for me. Have ordered some white LEDS and will try the green Bootie trick.

Just an update-