Dash lights go out during driving. sometimes are out when the vehicle is started - sometimes come on then go off again.  1999 kia sportage 4wd

Towing

Kia lists a maximum trailer towing mass (trailer plus load) of 1800 kg for the Sportage but that figure would be illegal in NSW. For light commercials (such as the Sportage) in NSW, the regulations state that the loaded trailer must not exceed 2/3s of the gross vehicle mass (GYM) of the towing vehicle. The Sportage's GVM is 1928 kg, resulting in an allowable maximum towing mass of 1292 kg. Even this figure could be beyond the Sportage's reasonable capabilities, given its sub standard handling and its overall levels of performance.

The actuator on the transfer case has a ground short. This is why the light is on. And it will try to shift back and forth, if you have the switch at 2wd.

Something is engaging the 4x4 on you. Check the vacuum hoses the wiring to the T case for shorts.

ALL NEW VECHICLE HAS ABS BRAKES SYSTEM.IF YOU HAVE 4WD DRIVE LOOK UNDERNEATH VECHICLE IF YOU SEE 2 DRIVE SHAFTS FRONT DRIVE SHAFT REAR DRIVE SHAFT YOU WILL HAVE 2 DIFFERENTIALS AND YOU WILL HAVE 4WD CONTROL SWITCH DASH OR CONSOLE.

with 4wd engaged check that the front tailshaft to the diff does not turn more than 45* if this is ok and no 4wd light check bulb switch and wiring. if light ok you will need to track down vacuum leak to drive hubs fault { common fault } you can check 4wd operation by raising one front wheel with handbrake on and car in netural select 4wd with engine running if 4wd ok raised wheel will not turn more than 45* by hand and will spin free when 4wd disconnected

If it is automatic transmission you must stop vehicle put it in neutral or "n" then put shifter that is indicates 2h 4h and 4L pull down to 4h if you are driving on highway or pull down then over and up to 4L if you are not going to be driving faster than 30mph.
If manual put in neutral also and do the same process as automatic there will be a light on dash board indicating that it is in 4wd also put transmission back to drive on automatic or shift to first gear on manual

It sounds like your CV joints, on the outsides of the front axles, are binding up. You might end up having to replace them. A small piece of advise, drive about a mile or so once a month in 4WD, that will help prevent this from happening again.

cv joints maybe ball joints maybe transfer case but i dont think it is

replace vacuum hoses they are located just out side shock towers front end

We unhooked the battery and left it unhooked all night. This morning when he reconnected it and started it, it started right up and the hold light and our check engine light went off. We did press the hold button and it came on and went back off when we hit it again.