What does it mean when your gages all sweep right upon startup, then return to the left after a one second pause? It "sweeps" just like it does when you're doing the self-diagnostic/digital speedometer trick.

Seems odd - the truck just started doing it the other day.

Thanks for any help - I'm baffled.

 

The needles to a full sweep on the next startup after you disconnect the battery (reset the computer).

 

check the chip, sounds like the chip may be loose

 

Maybe you got a Pontiac... they all do that.

 

They also do that if you're losing power to the PCM between runs, check connections.

 

It means you have a bad battery, I just went through that and found a bad cell in my Ford Battery after 4 years so I boughtb another one since it still cranked on the bad one.

 

yeah I like that they do that. I was hoping this thread was going to be about how 2 make the needles sweep on start up. Mine only does that when I disconect the battery I know. I wish it did that everytime I started the truck up... good luck getten the problem fixed.
Thanks, Shane

 

Ive heard of the self diagnostic trick. How do you exactly do it? Will it work on my 99 L?

 

While holding in the trip odo button turn on the key and continue holding in the button. After about 4 secs it will say "test" in the odo display. Start(or not) the vehicle. Everytime you push the odo button it will switch to a new function(the 2nd one is the full gauge sweep minus the analog boost gauge). After going through all the functions it starts over. The one that reads"ENG0000" is a digital speedometer that continues past the 140 mark unlike the normal speedo needle that stops at a hair past 140(anyone that has told you they had their needle down to the "D" on the gear selector or so is yanking your chain). Turning off the key returns everything back to its normal functions.

 

sweet! Thanks

edit just went out and tried it... Some of the different modes i just dont get... Is there a list out there that says what they all are? Also if when u do this can you start the motor and drive or what?

Sorry im still a newbie

 

yeah! thats pretty neat you can even check gallons in gastank disarm your seatbelt and alot of stuff with that menu .

 

Yes, you can drive around like that, it resets after you turn it off. As far as the codes you'd probably need a Ford manual to understand them all but this is the best description I've seen of them:

http://www.mustangworld.com/ourpics/fcar/dtcodes.htm

NOTE: Also click on link at bottom of the article for more info.

As far as I know ALL newer Fords with the digital odo will do it, even a regular F150.

 

that is MONEY!!!

I have to drive home in a few minutes, I'm seeing the Speedo in eal digital time!

 

Cool..

Back on topic though i do agree that it sounds as though you are loosing power to pcm. It may have a short, bad chip (loose) etc. I would start with the chip, but it sounds like the pcm is taking a dive on you. Has anyone altered the wiring harness recently? Aftermarket sterio, alarm etc??