I recently bought a 2008 jeep kk sport 4x4. And I used the 4hi once since I bought it. Today I was going to a fishing hole and there was some rough looking sand ahead so I figured I will switch the 4wd hi on. As I did I put the jeep in neutral, powered down the jeep,switched to 4wd hi and it sounded like it engaged but then the 4wd serv light pops up. So I decided to go home rather then go through any of the sand. I choose to do the other method of switching the car Into 4hi by powering it down just because the dealer told me to do that by preference. I got home and disconnected the negative on the battery for about 1min and went to check again its still on. Any suggestions?I had a guy tell me to back the jeep up about 100 feet and it should reset sensors not sure if that would help.   

Can you tell me what you mean by "powering the jeep down"?

You can switch back and forth from 2WD to 4HI at any speed, in any gear. No need to do anything special other than flipping the switch.

To switch into and out of 4LO you need to be stopped and in Neutral before flipping the switch.

It could be that your automatic t-case linkage is out of adjustment if it isn't changing over successfully and it is illuminating the Serv 4WD light.

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2008 Liberty Sport 4x4 Automatic

Jeepin By Al 4" Lift Kit
BFG KO2’s 245/75R16
Full MOPAR skid plates
Rock Lizard Skink Super Sliders
AtTheHelm Front Recovery System & Roof Rack
M116A3 Trailer build thread: viewtopic.php?f=72&t=77997

Had a similar situation with my '08 as well... Are you meaning 4lo instead of 4hi? You can shift into 4hi while the vehicle is in motion with speeds up to 40mph. 4lo you need to be in neutral... Jeep.com used to have a description and how to video for using 4wd (and I don't mean that offensively by any means) - check it out sometime.

Anyhow good idea would be to go someplace secluded and go through the motions to properly put your vehicle in 4lo - drive for 100 feet or so, and then shift out of it. If it doesn't properly shift into 4lo or the light remains on, might want to drop by the stealership, a lot of places usually don't mind taking a minute or two to check things out.

Hope this helps.

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When I say" power down" I mean by turning the key to the off postition. I did not know you can switch to 4hi any time under 40mph. I never owned a shiftable 4x4 only awds. No offense taken. Im new to all this stuff as I only had dodge 2500 and a motorcycle which was my main transportation. Thanks guys. I will be taking it to the dealer tomorrow to see what they have to say. But u will deffiantly try those ideas out.

FLKK here's that link on the info for the various 4x4 setups jeep offers. Depending on which setup you have here's the basics on how they work: http://www.jeep.com/en/4x4/

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Yes, it's good to know you can switch to 4hi on the fly, but I thought the mph mark was more at 50mph rather than 40. How many miles are on your KK? Maybe it detects the old oil?

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2008 Black Jeep Liberty Sport
4.7L throttle body
Old Man Emu lift
Sky Slider
Hypertech Max Energy
K&N CAI
Gibson stainless steel exhaust
Blacked out
ScanGauge2
BFG All Terrrain 225/75/16
JBA upper control arms

You're correct, it is up to speeds of 50 mph. I was regurgitating from memory and hadn't double checked the link. Honestly if you're needing 4hi at 50mph you should really double check your situation lol.

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65000 miles. Went to the services dept and they dont have a opening until the 20th. Now the light will come on for periods of time and shut off. They ensured me its not engaged in 4wd , but they never physically looked at it in a lift.

You also don't need to turn it off