2016 Yukon Denali. Vehicle got stuck in the snow. A ball was used in the hitch to pull it out. Next day the battery was dead. After jumping, it had the Service Trailer Brake System message. Didnt think anything of it except now the battery won't hold a charge. It will jump and run fine but left overnight the battery drains. The vehicle ran fine prior to using the hitch to pull it out of the snow. Could the brake system be causing the parasitic drain? Is there a fuse or relay i can pull to reset the trailer brake system? I've read there is also a module in the rear that could be the cause of the Service Trailer Brake System message but nothing I've read mentions the parasitic drain. Thanks for any assistance!
2016 DENALI/Battery drain/SERVICE Trailer Brake System
- Thread starter Eelimak
- Start date
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Need to get a DVOM and measure the amount of draw and then start pulling fuses/relays to see what circuit stops draining when the right fuse/relay is pulled. Then do the diagnostics on that circuit. When stuck and being pulled out, may have dragged under the rig to where something was damaged.
Need to get a DVOM and measure the amount of draw and then start pulling fuses/relays to see what circuit stops draining when the right fuse/relay is pulled. Then do the diagnostics on that circuit. When stuck and being pulled out, may have dragged under the rig to where something was damaged.
wjburken
Supporting Member
There shouldn’t be anything electrical involved with pulling on a ball hitch.
Not knowing how you went into the snow, how you came out of the snow, how deep the snow was, etc. hard to start guessing what it could be.
@MO VietVet has given you a good place to start with checking for any damage underneath and working through the fuses and relays while checking current draw.
It may be as simple as letting it thaw out as you may have some snow packed in somewhere closing a circuit and letting current flow.
Not knowing how you went into the snow, how you came out of the snow, how deep the snow was, etc. hard to start guessing what it could be.
@MO VietVet has given you a good place to start with checking for any damage underneath and working through the fuses and relays while checking current draw.
It may be as simple as letting it thaw out as you may have some snow packed in somewhere closing a circuit and letting current flow.
The being dragged out and damaging something is what had me thinking about the module in the back and the service trailer brake system message.
It's a clients vehicle that I take care. I was not there nor part of it getting stuck or unstuck so I cant answer those questions. It has been in a heated garage since, which was over a week ago. Too much of a coincidence to have used the hitch to pull it out, received the Service Trailer Brake System message and a drained battery after. I've read that there is a push for a recall on the brake system wiring as many people have issues with the light coming on. Was wondering if others who have the service light have had any issues with the battery draining.
It would be helpful to get the code that is being set for the Service Trailer Brake issue. That problem may or may not be related to the battery drain.
As far as pulling fuses goes, after you get the code you could pull the Trailer Brake fuse, as well as the Aux Power fuse that feeds the 7-blade trailer connector; both should be in the underhood fusebox. If there was damage to the trailer harness in back it could affect both of those circuits.
As far as pulling fuses goes, after you get the code you could pull the Trailer Brake fuse, as well as the Aux Power fuse that feeds the 7-blade trailer connector; both should be in the underhood fusebox. If there was damage to the trailer harness in back it could affect both of those circuits.
Joseph Garcia
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As suggested above, I'd really check out very closely the entire underside of the truck, to see if any wires appear to be out of place, due to being dragged out of the snow.
Maybe the Trailer Brake fuse is blown and that's why it's setting the code, whatever the code is....
they only way they could be related is if while pulling it out something yanked on the harness or damaged the module, get under it with a flashlight and take a good look around most of the harness goes down the drivers side to the rear left corner and then over to the right..
like others stated put a meter on it and monitor the voltage, there are many youtube videos out there on how-to.
have the battery tested anyway just to rule it out.
there is really no other advice anyone could give you, could a damaged module or harness cause a battery drain-maybe...but after 10 minutes the system goes into sleep mode.
like others stated put a meter on it and monitor the voltage, there are many youtube videos out there on how-to.
have the battery tested anyway just to rule it out.
there is really no other advice anyone could give you, could a damaged module or harness cause a battery drain-maybe...but after 10 minutes the system goes into sleep mode.
Did you figure out the problem? And what fixed the issue
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