I recently bought a 2003 F150 xlt supercab with the 5.4 L engine. When I was looking at the truck it had the light on, the car lot had it checked out with there mechanic and a sensor was replaced. The next day I drove the truck again and the light was off and ran fine. I have had the truck for about 2 weeks and the gas cap loose light was on for a few days, so I took the truck to parts house and used there code reader to reset the light. While I was reading the codes I saw a code for evap system, so I figured it was because the light stayed on so long for the gas cap, I cleared all the codes. The next day I got to thinking, so I put the key in the ignition and turned it to the on position and no service engine was on, and at no time does it ever come on. I believe the light is suppose to come on to check the bulb when the ignition is on at least. I took the instrument cluster out and didn't see a bulb for it. My question is, is that bulb user replaceable? or is it possible the car lot or the mechanic disabled it some how. Any help on this, would greatly be appreciated.

Thanks

 

Yes there should be a light with engine off and ignition on. Would think that a bulb has been removed. Try another bulb from near by, if it physically fits than thats the bulb.

 

idk but it sounds like they may have took the bulb out or something ot me mine comes on when i switch the key forward i think they are suppose to

 

I took the whole instrument cluster out yesterday and only seen one bulb on that side of it. There is like 4 or 5 light on that side of the cluster, but on the back of it there were alot of holes that I could see the circuit board through, but only one hole had a bulb that I could remove. The bulb looked ok and it was up too high to be the service engine light bulb. I didn't see any holes where a bulb would be missing or something. The dealership this morning told me the bulb is built in and not user replaceable that I had to get a new instrument cluster. Not sure if I believe that, but don't see a bulb to replace either. I am wondering if there is some way to disable it through a programmer or reader or something maybe. Not sure what to do, and hate to pay $600 plus for a bulb.

 

I didn't know there was a separate light for a loose fuel cap? Doesn't the service engine soon light come on when that happens?

 

My service engine light is on the left side and the gas cap loose light is on the right side of the panel. I believe if the gas cap light problem isn't solved quick enough the engine light comes on at that time.

 

Interesting comment by the dealership. Its almost believable with the emissions testing required. Tried once to get to my parts guy for more info, can't get thru, will try again.

 

Ok, thanks Bill. I really appreciate it.

 

Finally got thru, he doubts what the guy said, because of the price of the cluster is like $300.00. Hopefully the panel is still out for another look see. Speaking of which did you remove the circuit board from the cluster? The ones I have seen the bulbs engage directly to the circuit board.

 

Well the cluster he said was $322 and 3 hours labor and another key to be made because I only got one key with the truck and the programming came up over $600 total. I had to put the cluster back in and dash back together yesterday, in order, to go to work today. I did not remove the circuit board from the cluster.
I figured all the replaceable bulbs would be accessible from the holes in the white plastic piece on the back of the cluster. The holes on the back that had bulbs were black caps holding the bulb and screwed into a hole in the circuit board. I had to use a pair of needle nose pliers to go through the hole in the back and get ahold of the socket to remove the bulb that I took out. The closet bulb to the light was probably about 3 lights up from the service engine light and the bulb looked good and all the other lights on that side works fine.