06 LC Center Diff Locks Randomly

[Ben Sawyer]

Wife's 06 LC center diff locks randomly. Usually right after she turns it on. It usually takes several attempts to get the CDL to disengage. We're the original owners and started happening about 3 years ago. Happens about once a month. Dealer has no idea why. She's not engaging it in error as it has happened to me as well and the diff was definitely locked when I drove. It will engage and disengage normally when we initiate it. Car only has 98K on it and hoping to keep it for at least another 98K , but she wants me to sell it and get her a Q7. I'm not ready to give up on it yet. Can't find any forum that addresses this specifically. Hopefully someone on this site knows of a possible fix.

Any help would be appreciated.

 

[StarCruiser]

Hi Ben and welcome. We're a friendly bunch on here and like people that are friendly too so it's good to have a bit of an introduction, say hello that sort of thing.

It's either a fault in the switch or a wiring fault. Think back to the time it started, did anything happen to the truck out of the ordinary? Have you tried disconnecting the switch in the dash and see if it still happens? Have a look underneath the truck around the gearbox/transfer box area for any damaged wiring. If it still does it reconnect the switch in the dash. Locate the connection under the truck into the transfer box and unplug it and put it in a bag taped up along with where it came from and see what happens. If neither of these cure it, it's a wiring fault (or possibly a controller depending on your truck).

Good of luck with it.

Richard

p.s pop over and introduce yourself and tell us a bit about you and your truck

 

[BobMurphy]

Some years ago I had a brand new Ford Focus Estate. Occasionally when on full lock the tailgate would unlock - it went back to Fords and they re-routed the wiring. It didn't happen again after that.

Does your CDL engage when you are turning or doing something that could be tugging at the wiring loom ??

It sounds as though there is something like that going on.

Bob.

 

[Ben Sawyer]

Thanks for the insights. You're thinking what I have suspected which is it is a wiring issue. There's no consistent event that causes the CDL to lock other than it happens upon starting the vehicle. I'm going to pursue the wiring suggestion and I'll report back what we find (if anything).

Thanks so much for your help!

 

[uHu]

I've had a fault in the wiring-loom, resulting in the CDL actuator motor activating. The wires from the diff.lock relay run through the engine loom and down and back to the x-fer box. My guess is either a loom problem, which could be aggravated by the running of the starter; or, more probable, a grounding problem of the engine, which would make some of the starter current run through the CDL actuator motor, or through the relay.
Check the ground strap on the RHS engine mount going to the rhs battery. Take it off, clean the surfaces, and reattach it really well. Is this a HDJ100? Then there is also one from the LHS battery to the lhs of the block, iirc.

Please give us some more info on your car - like engine, gearbox, model, version, extras, location(market) etc.

 

[Ben Sawyer]

Thanks. I'll let you know what I find out. I know it's something like what you describe. The vehicle is a J100 4.7 V8 5 speed standard U.S. model. No mods.