GM Duramax - NO Trailer Brakes

[pcm1959]

I have a 2013 HD with the factory integrated trailer brake controller. Today when I plugged in the fiver, NO brakes.
The DIC shows nothing but the the gain set point. I can adjust the gain up and down. No messages such as "trailer connected or trailer disconnect" nor any chimes.
There has been an occasion when I plug-in in the umbilical cord that I have had to jiggle it or unplug it and re-plug it to get a connection but that is rare. Once its connected I have never had an issue. In addition I do have the in-bed plug as well as the one near the bumper but neither would work today. I looked underneath but all the wiring looks fine.
All of the trailer lights work - turn signals and brake lights.
I connected a tester to the vehicle end plug to test the function of each blade. When I tested the brake blade, there was a very, very slight pulsing of the test meter needle even without pushing the brake pedal OR the manual brake control on the ITBC. Pressing the brake pedal or manual control made no change.
I do have e/h Dexter disc brakes on the fiver with the HBA-Cam adapter for the disc brakes. I checked all the wiring connections and they all looked fine.
I pulled the trailer on Friday with no issue. The trailer and truck were parked until today and now in 3 days, now no brakes.
Am I correct in that this issue is on the truck end since I am not getting any output with the test meter when testing the "brake Blade" on the vehicle end?
I checked 3 fuses......number 19 ITBC, 58 Stud 2, and 63 Stud 1. Number 19 is ok. The other 2 are fuses I'm not familiar with, however, compared to the others like it there was no difference in their appearance.
I plugged-in the RV again and no change. No messages at all on the DIC. Plugging and un-plugging the umbilical cord creates no messages or chimes.
Thanks, Phil

[pcm1959]

I appreciate all the replies. I just flew back into town for IRMA. This situation is not a huge priority right now, however, since the RV is at the house I was able to pull the break-away plunger. The brakes worked. So its somewhere in the umbilical cord, truck plug, or HB-CAM as Roger mentioned, or some other component of the truck. Great! I didn't realize they could go bad.
At least I know its not the trailer brakes like a bad pump or pump wiring.

[Hunterred]

Try pulling the emergency disconnect on the trailer to see if you hear the magnets, that will at least prove it to a truck problem. After that, short of a fuse problem, which is most likely but doesn't seem to be the issue in this case, you may need professional assistance. Like google!

[Roger10378]

It sounds like you either have bad wiring on the trailer or the HB-CAM has gone bad. The pulses you are seeing at the truck connector is the controller checking to see if there is a trailer connected. When it does not see the resistance of the brake magnets it assumes no trailer. The HB-CAM is needed to simulate the brake magnets so that the controller will operate the hydraulic pump.

[Paul_Clancy]

I'd try disconnecting batts on the truck and let sit for .5hr then reconnect. Try your tester. Then if good try trailer connect.

[Jacksons]

pcm1959 wrote:

salem wrote:
IIRC, my '16 Chevy doesn't show a connect icon on the DIC. It just shows the gain. It moves when I step on the brake. I'm assuming yours is the same. If it wasn't connected you would not be showing that. It's too darned hot to run out and hook up the 5'er and verify that so maybe someone else can jump in.:) On my old truck, which had a Tekonsha unit in it, a large "C" would show in the window when hooked up.

Must have changed on the 2016. My 2011 and this 2013 gives messages anytime its connected OR disconnected. In addition, a graph is displayed in the DIC as the brakes are applied either with the pedal or manually.
I am getting nothing just as if its never been connected. All functions of the plug are working (all functions of lights including brake lights) except the brakes.

my 2016 chevy gives me a trailer connected on the DIC your seems to have a problem

[bobsallyh]

There was a thread on this a year or so go. That problem turned out to be a GM problem of some sort and the truck was out of warranty with about grand quoted for dealer repair. If I remember he simply got an aftermarket brake controller and installed it. I know if that were my situation, that is exactly what I'd do! Hopefully this doesn't turn out to be your situation.

[2003silverado]

KD4UPL Makes a really good point. I have a trailer with bad brake wiring and all lights work but the truck won't recognize the trailer as being connected. When my fuse 63 blew, I had a continual "service trailer brake message" on my dic whether or not the trailer was connected. When you get through Irma if you have access to a friends truck you might plug your trailer into it and at that point you could determine which is the problem.

Our best wishes and prayers are with you and the state of Florida.

[KD4UPL]

I would guess an open connection somewhere. It could be on the truck but I would suspect the trailer first. Trailer wiring I've seen is usually not as tidy and well supported and fastened as most new truck wiring.
On my '15 Chevy the display says trailer connected and trailer disconnected when you plug and unplug IF the trailer brakes are functional. If they aren't then it doesn't know. If the trailer brake wiring develops a short it gives me the message "Service trailer brakes". Since you don't have that I suspect an open, not a short.

[pcm1959]

2003silverado wrote:
When my fuse 63 blew it exhibited the same symptoms as yours, to my eyes it looked good but when I put an ohm meter on it, it was no good. When I looked through a magnifying glass I could see the crack in the copper.

I'm not trying to beat a dead horse, but the naked eye can't always determine a failed fuse

I appreciate that. As I mentioned, not being familiar with that type of fuse, It appeared normal. I will check it more carefully or perhaps just replace it.
I have To deal with Irma now but will post what my results are.
Thanks! Phil

[2003silverado]

When my fuse 63 blew it exhibited the same symptoms as yours, to my eyes it looked good but when I put an ohm meter on it, it was no good. When I looked through a magnifying glass I could see the crack in the copper.

I'm not trying to beat a dead horse, but the naked eye can't always determine a failed fuse.

My truck is a 2012. You could swap fuses with a similar one to see if it makes a difference..

[pcm1959]

2003silverado wrote:
Check fuse number 63 in your under hood fuse box. It is a 30 amp large square fuse.

"I checked 3 fuses......number 19 ITBC, 58 Stud 2, and 63 Stud 1. Number 19 is ok. The other 2 are fuses I'm not familiar with, however, compared to the others like it there was no difference in their appearance".

Thanks....did that already.

[2003silverado]

Check fuse number 63 in your under hood fuse box. It is a 30 amp large square fuse.

[pcm1959]

salem wrote:
IIRC, my '16 Chevy doesn't show a connect icon on the DIC. It just shows the gain. It moves when I step on the brake. I'm assuming yours is the same. If it wasn't connected you would not be showing that. It's too darned hot to run out and hook up the 5'er and verify that so maybe someone else can jump in.:) On my old truck, which had a Tekonsha unit in it, a large "C" would show in the window when hooked up.

Must have changed on the 2016. My 2011 and this 2013 gives messages anytime its connected OR disconnected. In addition, a graph is displayed in the DIC as the brakes are applied either with the pedal or manually.
I am getting nothing just as if its never been connected. All functions of the plug are working (all functions of lights including brake lights) except the brakes.

[pcm1959]

Mine says "Trailer connected or Trailer disconnected anytime you plug it in or unplug it. Doing either also produces a chime. I am getting no message or chime when I plug in the trailer OR unplug it.
Pressing the pedal or using the manual lever produces nothing on the display like it normally would not does it produce any output to the brake blade on the truck end plug.

[salem]

IIRC, my '16 Chevy doesn't show a connect icon on the DIC. It just shows the gain. It moves when I step on the brake. I'm assuming yours is the same. If it wasn't connected you would not be showing that. It's too darned hot to run out and hook up the 5'er and verify that so maybe someone else can jump in.:) On my old truck, which had a Tekonsha unit in it, a large "C" would show in the window when hooked up.