Need to check the charging system. sounds like a bad alternator.
replace the alternator
what causes the battery light to on a 2005 ford expedition to come on?
You have a bad alternator.
you need a new alternator
It has a timing chain that requires no maintenance.
probably have a bad alternator or voltage regulator or bad battery cables
This indicates a no-charge situation. Most likely the alternator is bad.
check fan belt is not broken or loose and check alternator
sounds like your gauge is broken or there is a short in wiring
i have a 1998 and its in the fuse box
A person can reset the service engine light in a 1998 Tahoe by disconnecting the battery cables for 1 minute. After the battery cables are reconnected, the light should turn itself off.
Dead cell in the battery which will require it to be replaced. Or, you may have a light on somewhere pulling power from the battery. Can also be a relay that is stuck.