Just replaced battery and alternator in my 2006 Expedition.
It is on the battery charger still and hoping to make it to work and back tomorrow.
Even after replacing battery and alternator still show P0266 and lights check charging system and lites up battery indicactor on dash...
Any known issues ?
Places to start?
Appreciate any tips.
THANKS

 

Check the link, good information............


http://www.obd-codes.com/p0266

 

Is your code p0266 or p0622? I am fighting with the same problem since changing my alternator in my 06 expedition. I put one in off an 05 I had and it charges but gives the p0622 code. Put a reman jobber and had the same issue. Put a different one off another expedition and same again. They all charge but throw the code after a minute or two of running. Also seem to have a large battery drain that started about the same time as the alternator issue but it is still there even with the alternator unplugged.

 

Yep, good catch.
It is actually P0622, not what I mistakenly titled the thread.
OOPS
Close to returning home last night, info center flashes check charging system, beeps, and lights up red battery light on dash.
Pull in driveway and won't restart.
Check battery with load meter and low.
Put starter/charger on and restart.
Doesn't seem to be any better.
Battery has seemed marginal since I bought this 6-7 months ago.
And did not look like there was any more voltage when I got it running.
Compared load meter actions to my 2004 Expedition and thought it looked like an alternator was needed.
Replaced battery thinking I would cover my bases and it did not fare any better on the load meter after charging still.
Replaced alternator and battery both.
Figured I would hit key and no more warnings.
Nope.
Truck started and acted fine but still same warnings on dash.
Everything looked good and better with load meter and seems like it is charging.
Got my phone with Torque app and thought I would reset.
Nope, comes right back.
Threw jumper cables, some tools, and spare battery in back and rove to work today.
An hour on highway, 60 miles and still showing warnings.
Tried clearing codes a few times.
The dash gauge for battery looks good.
Torque app shows voltage 14.1 to 14.3 for whole drive in.
Is it just going to take time to reset itself?
Thinking with an hour of bright lights on, wipers going, and everything else drawing that I would not still be seeing 14+ volts if alternator was not operational.
d_loeff THANKS for catching my messing up the code#.
I am not thinking that I have a big drain happening, but with brand new fully charged battery I just may not be seeing it yet.
Hoping that is not the case and I just need to reset code now...
Fingers crossed anyways.

 

If I knew how to edit the title I would...oops

 

Check to see if fusible link C is burnt or not. See the attached PDFs.

 

If you're seeing 14.1 to 14.3V on the battery posts when engine is running, the alternator is working. Did you replace the alternator with an OEM one or an aftermarket one?

 

Thanks for the pdf's I will take a look.
Read a lot about grounds and clean mounts for the alternator.
Will look closer at those too.

My voltage reading came through my phone by way of the OBDII port.
New alternator was from Autozone, "premium reman".

 

Wondering what the differences are between the part # for my 2004 and 2006 Expeditions now...
Both 100 amp, but different part #s and the one I put in the 2006 shows for a 2004 model...?
Hmm???
Everything fit OK and did not see any differences.
Wonder if it operates wrong for this truck??
hope not.

 

The Expedition got a new upgraded engine and lots of electronics in '05, so I don't think an alternator from an '06 will work in an '04 and vice versa. They might physically bolt on, but the electrical connections will most likely not be compatible.

 

You are right, it did bolt in.
The wiring and connectors were all the same too...
Seeing the different part #, I wonder if that is causing the light and code or if I have another issue???

 

Picked up the correct alternator yesterday and no more warning lights or codes.
Lesson learned.
The 2004 and 2006 parts look identical from the outside.
The 2004 alternator bolted on, plugged in, and actually charged, worked, but threw the code and lit the battery light on dash up.
The wiring connectors are same and everything.
Kind of surprised that something would not have been done to keep from allowing a mix up.
But...
I guess I should have known, been more careful, and worked harder to ensure I had the correct stuff.
APPRECIATE all the help ! ! !

 

I know the newer alternator is controlled by the PCM, and I don't think the older ones were.. The older ones I think had a more traditional design, which is why it charged but the PCM was not happy and threw codes since it didn't get the right signals and couldn't control it.

 

After everything that I have "learned" now, I would guess that something along those lines must be the case.
Pretty amazing how "smart" and linked together everything is.
Modern Technology
Impressive, but makes me appreciate my 1975 Bronco at the same time too.
Thanks for all the help !!!

 

Hehe, yeah. The old stuff just worked, the new stuff has all this electronics to make it more efficient, but at the same time there's more stuff that can go wrong...