Trailer Plug

[Bill Fielding]

Can someone explain to me the plug configuration on this. I thought I should have the standard 7 and 4 pin hookups but have these 2 top cylinder type plugs. The 7 pin is there but no 4 pin flat wire option. The dealer told me it has something to do with a HD camera upgrade, but didn't know much more than that and can't find anything in owners manual.

[snork]

camera plug in for the trailer

[smrr1]

Looks like you will need to get a 7 to 4 pin adapter like on the older trucks. I guess the trailer camera takes away the 4 pin. Can't have it all! 

[davester]

Did you even read through the owners manual.  It took me less than 5 minutes to find it in the owners manual.  Hint:  It's in the Driving and Operating/Trailer Towing section (at least in the 2020 manual, probably the same in the 2019 one).

 

It might seem like you know all the stuff GM would put in their owners manual, but you probably don't.  Try reading the whole thing.

[Bill Fielding]

I did read through my manual and it is not there, you assumed something.... you know what they say about people who assume!

[davester]

3 hours ago, Bill Fielding said:

I did read through my manual and it is not there, you assumed something.... you know what they say about people who assume!

Maybe read more of it?  It has 3 pages on just the trailer electrical connections, pictures of the various plugs, when to plug and unplug them.  It even explains why you don't have a 4-way plug.

 

It even has a table of contents and an index to make finding specific things easier.

 

 

Edited January 19, 2020 by txab

[txab]

Ok. Everyone take a breath, and let it go.

 

Manuals change from one year to the next. OP doesn't state what year he has. 2020 manual does address this. Prior years may not

 

 

Quote

 

If equipped, trailering camera connectors are available in the bumper trailer receptacle in place of the four pin connector. The inside trailer auxiliary camera should be installed on the top left hand   side (A) and the rear trailer auxiliary camera (B) should be installed on the top right hand side.If equipped with the fifth wheel/gooseneck trailer package, the harness connector is mounted on the inside of the pickup bed behind the rear wheel.

 

 

Edited January 19, 2020 by txab

[billybob denali]

my 2020 sierra (denali) trailer plug receiver seems faulty... the brake and turn signals work, no side lights. DIC says pin # 4 (sidelights) and # 5 are not working. The trailer has no electric brakes, so that makes sense... when I plug in the boat trailer, the side lights will light up for 1-3 seconds, then go off.  Has GM has issues with these receivers?  corrosion? Also the security flash on the tail lights used to flash about every 30 seconds... not there seems to be no pattern of duration, but constantly studder/flash more random.. is the receiver corroded?

 

UPDATE: plugged the trailer into a neighbor's GMC (2018) and all lights stayed on. One left side light was out, the other 3 were on. I ticked the LED sidelight and it came on... all light functions performed correctly. Then plugged into my truck and all side lights lit up... I think the 2020 connector/software on my truck "sensed" a sidelight was out and then just shut down # 4 pin. The older truck didn't shut down #4 pin.  All is ok now,,, I just wonder what the actual software is in that plug or operating system?

Edited June 27, 2024 by billybob denali

[repairman54]

Full system code scan is step one. All 4 code families, so you can see what all the onboard modules are reporting. 

Without a full scan first its a guessing game with todays computers on tires. It's what every shop does.