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EwWhat does Service 4wd lightw mean?wyesd

5K views 36 replies 8 participants last post by  beech2000 
#1 ·
Needed 4WD low this afternoon pulling out a 16,000 lb Sea Ray on a slippery boat ramp. Nope not today. I received a 4WD service light when selecting. Truck is a 2012 Mega G56. What does the hell does this light mean and why won't 4WD work?
 
#2 ·
Electric servo on transfer case not engaging possibly? Thsts whst happen to mine few years back. There has been many discussions with others similiar failure.. It was a quick fix from dealer. Hope thst helps.
 
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#3 ·
What was the cost? And what did they find? I'm about tired of these types of issues. This will be the third electrical problem since purchased in June.


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#10 ·
I had great luck with my 03 this one is possessed with electrical issues. Still love it but broke.


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#11 ·
The way we feel about our trucks can be up or down depending. Mine has taken a small hit in the way I feel but time heals all wounds. These are the best trucks made.
 
#12 ·
With the electrical 4x4 it could be a fuse/relay, the connector behind the switch could have vibrated lose, wiring shorting out or broke. Most times it's the motor on back of the t-case. Try rock auto they might have one, two bolts and a connector and you're done. Orielly's may also carry or get it. Also check the servo on the front axle.
 
#15 ·
What does Service 4wd light mean?

Backed down ramp in 2wd. Selected 4wd low. Service 4 wheel drive light illuminated. Selected off. Light stayed on. Connected loaded boat and tried in 2 wheel drive. Nope not enough traction. Backed down again. Light stayed on. Tried moving to 4 wheel high. No change. Move it to off then 4 wheel low. Truck stayed in 2 wheel drive. Unloaded boat. Went home. What can I check for? No OBD codes display with key on off on off on???


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#17 ·
When you selected 4low did you hear any noise coming from under the truck. Most all times when selecting 4low you will hear a slight clunk. If you have a test light back probe the connector on the t-case motor to see if power getting to it. Have someone to move selector while you do this. I can't recall wire colors. If you are getting power there then its most likly the motor. If not then back up to the selector and see if you are getting power there. If you hear the "clunk" then you are getting power to the motor, check the servo on the front axle see if it's getting power.
 
#19 ·
This morning i went at diagnosing the situation. As soon as I turned the key I heard a thump. No light now and confused.


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#29 ·
Why does the truck stop rolling from gravity when rolling downward on ramp in 4WD high. Wheels were slightly turned to straighten truck?? Almost like brakes being applied... I pulled 9 boats out today at Lake Lanier. One was 28,000 lbs. Walked it out perfect $$$
 
#31 ·
Any pics of the boats connected to the trucks? There are tons of 5th wheel pics never any boat pics.

Glad to hear the 4x4 works. I've always preferred the manual shift transfer cases but these days everything in the modern day diesel truck is so electrical.....
 
#32 ·
What does Service 4wd light mean?

Never thought to take one. To electrical reliance and glitchy


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#33 ·
That's why I got a tradesmen, manual transmission and manual shifted 4x4. I think you can order a manual transfer case in any of them though. Is the ramp solid concrete or in foot wide sections with about 3 to 4 inch gaps?
 
#35 ·
Hmm might have to look into a tradesman.
Ramp is solid but slimy concrete then at top turns to worn out tarmac (asphalt) and mostly flat at top.


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#34 ·
This is also why I got the Tradesman/ST edition of my truck...less electrical nightmares down the road.
I drive a F superduty dually (gas) for work and compared to my buddies 5.9 (12v) Cummins manual is like night and day. F-Dually is all electrical vs the Cummins all mechanical.
I'll take a Cummins (even the electric shift ones) anyday
 
#36 ·
Got me on the rolling back part, unless trailer tires are coming to rest against something. Yeah you can upgrade the interior with cloth seats, 8.??? Radio ext.
 
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