[Archived]

I beleive they have an electric power steering pump. That is why the battery needs to be disconnected; it started in the 2015 models.

[Tim]

When he or she unhooked the negative/ground Cable at the battery, won’t that kill the clock and anything else that’s using some low level amount of power to run? Upon reconnecting the battery won’t the user need to reset the clock? Maybe the radio stations? Or is all of that in some kind of none volitile memory?

A heavy duty racing battery disconnect switch from Longacre wired into big ground/negative wire etween the battery and chassis should get the job done.

[Reagan]

Dick,

Those are some of the questions we are trying to get answers to. The owner’s manual does not give that info as far as we can tell.

[Dick]

The real problem is the steering wheel lock that GM put back into vehicles. You can tow it, but you must follow the instructions in the manual. I tried to get my GM dealer to remove the lock, but they would not do it.

Yes, you do loose memory settings. Diane Byrd can tell you about how they are working around some of the issues with the newer GM vehicles.

[Eric]

New car/truck. Take it back to the dealer and ask them the ramificaitons of disconnecting the battery. Or disconnect and see what happens. The service manual for the vehicle probably outlines what happens when the battery is disconnected and what has to be dealt with to bring the vehicle back to what it had been prior to the disconnect.

[Archived]

Dick, the manual is very specific on what to do and the order in which to do it. What it does not say, is anything about what you have to reset after the battery disconnect. I went round and round with my dealer when I got my Denali and they did not know anything or want to do anything. So I bought the Jeep to tow and said the hell with trying to tow the Denali. There are many people towing Tahoes and Yukons.

I talked to a couple of owners who said they just don’t bother setting up anything that resets with a battery disconnect.

[Mark]

Mark is correct The reason for battery disconnect is to prevent steering wheel lock from engaging. I have towed many different vehicles thru the years and this 2015 Tahoe is by far the most hassle when hooking and unhooking the tow. I have yet too lose any memory settings in the radio etc It apparently has an internal battery that maintains the memory. I had to have a chevy dealer reflash the transfer case software in Florida on our first trip with it.

I believe GM used to make good stuff until Obama Motors took over!

[John]

Roger,

That’s why I bought a Lincoln (not all Lincoln’s are towable). It has a ‘tow-neutral’ mode that you select when towing. I haven’t towed it yet as I just got it set-up with the base-plate, SMI, etc.

The MKX is a roomy comfortable car that seats 5. It weighs about 4,200 lbs.

Safe travels,

Mark

[Tim]

I have a 2017 GMC YukonXL Denali that I tow. This truck proved to be a big pain to get to set up for towing.

Our prior Suburban was much easier. This was my work around for having to remove the negative terminal when towing.

I installed a Roadmaster Battery disconnect #766 that installed nicely under the hood, so I could remotely disconnect the battery while sitting in the drivers seat. I mounted the relay on the air cleaner top. now there is no need for wrenches everytime you needed to remove the negative terminal. I placed the remote switch on the left lower dash as it was easy to run the wires through the firewall in the hood release grommet.

I have a M & G brake system and have this hard wired to the battery by placing the negative lead from the M & G to the battery neg terminal connection on the Roadmaster relay. so the M & G stays on all the time I tow even though no power to the vehicle.

The back lights/turn signals hard wired to coach via 6 pin trailer plug, and diodes in the back wires to the LED lights.

Then the problem of turning the truck off and losing seat pre-sets, radio, etc… Diane Byrd on this site had posted about using a 9 volt battery plugged into your accessory cigarette lighter to support the electronics. In my particular truck the 12 volt plug between the seats was not live when the truck was turned off. In order to make back feed to the electronics when the truck was turned off, you have to move a 50AMP fuse that is located on the left upper dash fuse panel when you open the drivers door. You take the 50AMP fuse from slot 5, and move it to slot 6. It is just to the right of slot 5. Then when you tow, get a 9volt battery to 12 volt cigarette plug in, and plug this into the accessory 12 volt plug in the center console. (available on amazon) I have had on occasion towed for over 2 days and have had the 9 volt go dead. I only lose seat presets, and the A/C temp goes to 32 F and get an ICE warning. You also have to reset the drivers and passenger window auto up feature by just rolling window down, and up. I have yet to lose the radio presents.

My truck has the remote keyless entry which caused more issues. The owners manual for 4 down towing is completely wrong.

REMEMBER , THIS IS THE PROCESS IF YOU HAVE REMOTE KEYLESS ENTRY !!!

This is the process that works for me:

To Hitch up:

1. Pull truck up to back of coach, apply parking brake

2. attach tow bar, air line, trailer plug cable, safety cables , and breakaway line

3. with truck runnig, Shift transmission column shifter to neutral.

4. Turn tranfer case knob clockwise until the rotation stops, and hold in that position for 10 seconds min, and the neutral light on the knob will blink. Info screen on the dash will report the shifting of the transfer case.

5. Verify that the transfer case is in neutral by shifting the column shifter to drive and reverse. there should be no motion of the truck. leave the column shifter in the drive position.

6. Shut off radio, AC, auto lights. Plug 9 volt battery into the cigarette lighter in center console.

7. Keep door shut and turn off the truck at the push button starter button on dash.

8. turn off truck battery at the remote switch. (Roadmater relay to battery)

9. Place column shifter into park. check steering wheel to make sure it is not locked by turning back and forth.

10. release parking brake !!!!!!!!!!!!

11. exit truck, lock with key as the remote will not do this.

The Un-Hitch process

1. open truck with key, set parking brake.

2. turn on battery back on at remote switch. Remove the 9 volt battery from center console.

3. DO NOT PUT FOOT ON BRAKE PEDAL. Push and hold dash starter button down for at least 15 seconds minimum. ( this will allow the transfer case to operate without the engine running) release starter button. Center screen and dash screen will come back up.

4. place column shifter into neutral.

5. shift transfer case to 2High position by rotating knob counter clockwise. Tranfer case will shift and notice will be given on dash screen when shift has occured.

6. start engine, shift column shifter into reverse, drive, and transmission should engage and give motion,. Shift column shifter into park.

7. reset drivers seat, window auto close if indicated.

8. Turn off truck

9. Disconnect from coach tow bar and all lines.

10. Release parking brake and truck is ready to hit the road and give off a nice rubber smell for a while.

(note: If you follow the direction in the manual and start up the truck , and try to get from neutral to 2H, the transfer case will grind, Not at happy sound !! by not placing foot on brake, and depressing the switch the electronics go into a “Service Mode” thus allowing the transfer case to shift without engine running)

I have towed the Yukon about 6,000 miles so far since I got her, and she tows like a champ. Mileage is not accrued , and M & G is awesome for the convience of use.

[Per]

what happens if the battery terminal is not disconnected?

[Larry]

if the battery is not disconnected the steering wheel remains locked. No key in the steering column.

[Philip]

We found that removing fuse #38 on the driver’s side fuse panel will disable the steering wheel lock. Have not yet found anything adverse from removing the fuse. Not yet sure if that action makes disconnecting the battery unnecessary.

[Ron]

Per

Any noticable problems after removing the fuse. after reading this post I removed the fuse #38 on our 2015 Tahoe,We have driven the vehicle but have not towed it yet, I did not notice anything different in driving and it did not change anything except the steering wheel does not lock. The steering wheel lock is the big PIA on towing this tahoe. after pulling the fuse I did shift the transfer case into neutral and back to drive several times, everything worked correctly and the transfer case did not lock up in neutral as has happened several times in the past.

And yes GM’s directions in the 2015 owners manual are not correct or complete. I got good instructions from a dealer in Chandler Az.

thanks to all

Glenn

[Archived]

Per I tow a 2015 GMC Canyon and yes I have to disconnect the negative cable from the battery, It’s no big deal as I bought a quick disconnect which I have to turn about 2 turns. I do not loose any radio stations and after I reconnect the negative cable the message on the DIC says to open and close the drivers window, which resets everything. It’s a very quick process and have had no problems.

[Doug]

We just got rid of our 2006 Envoy Denali last Oct. It was simple to put in neutral. Now everything out there you have to disconnect or pull something, run no more than 65 mph, and stop every 4-5 hours and let the toad run for 15 minutes. I like my Ram and bought my Jeep Grand Cherokee Summit because they are sooo easy to put in Neutral and flat tow. All you have to do is have it running in Neutral with the brake on, push the neutral button. DONE. Do the same to put it back in gear

Our Envoy had so many mechanical and electrical issues and GM wouldn’t do anything about it. The rear end went out on the road at less than 70,000 miles on the odometer and less than 20,000 towed miles. We followed all recommend services. Needless to say, we will not buy another new Government Motors product.