I have a pathfinder, when I press the button for the Altimeter or the Barometer it just says ERR

Timex Helix ABT.
This watch calculates altitude by measuring air pressure and relating that value to the international standard atmosphere. 1013.25 mb = 0 metres.
The Timex ABT does not display negative altitude values. So if the measured air pressure is greater than 1013.25 mb and the altimeter is reset (select altimeter, pull out the crown 1 click and press and hold the lower left button) the watch will display LO. You can experiment with this. Wait till the barometer reads 1013 or 1012 and reset the altimeter. The watch will display zero or maybe 5 metres. Or wait till the pressure goes up to, say, 1022 and reset the altimeter. The watch will read LO again. If this happens alot, you probably live fairly close to sea level. What you can do to trick the watch is use a vacuum cleaner to raise the perceived altitude of the watch then calibrate the altimeter (pull out and rotate the crown) and change the altimeter reading to, say, 200 metres. It wont read LO then. Keep an eye on it and the atmospheric pressure. If the pressure starts to rise then adjust the altimeter accordingly. Remember this watch is designed to measure proper altitudes where the air pressure isnt likely to be as high as 1013.25. If you are mooching around near sea level the naturally changing air pressure will often make the watch read LO.
If you live up in Montana at 1500 metres (ISA standard pressure about 840 mb) all the time then the watch will always read a positive value and you can calibrate it from reference to a map or road sign etc. The atmospheric pressure will unlikely reach as high as 1013 up there and the watch wont read LO.

Erik, the altimeter uses barometric pressure to determine changes in elevation. Rule one is whenever you know the elevation for a fact, adjust it as the barometer is changing often and therefore affecting the altimeter reading. The only sure way to avoid this is use GPS. Altitude is derived from locating 3 or 4 satellites in a geo syncrohnus(SP?) orbit. Pilots always reset the altimeter before take off and you should too. Find elevations on road signs, maps, etc.

Same problem with my SPF-40, module 2273, after a small helical compression spring, silver color, fell out. I could not determine where it is suppose to be located. It could be the barometric reference spring for sensing the barometric pressure.

you can get
instructions from the Casio web site.

Go to the casio web site "casio.com".

Select "support" and the "manuals",
watches;

Accept terms

Select "watch manual archive"

Read the number of the back of your watch and enter it into the search box

May I get the make and model # of the watch to help you more

here is the link for very complete manual:

http://ftp.casio.co.jp/pub/world_manual/wat/en/qw2271.pdf

Download it and follow the instructions how to set and reset the altimeter and other features of your watch. Use zoom or magnifying tool, as the document originaly has tiny script.
Do not forget to rate please.

Check watch caceback. All numers are there. Upload the numbers here and then we can help.
Use an eyeglass if numbers are too small.

wait until the battery is full reloaded

that old of a watch would need to be sent in. Send it into repairs and they will send you an estimate on what it would cost to fix it. Give them a call at 800-706-2534 option 2.

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