Whats this wire for?

L79racer

Original poster
Member
Apr 26, 2012
13
I was checking why my battery died and found this wire off. What is it meant for? Everything works in my truck. I know its not the cause just wondering why its off and do I need it on.

5posd1.jpg
 

Ray Dockrey

Member
Dec 6, 2011
15
It is not needed. It is only needed if you are pulling a trailer that has its own battery. It provides the power to charge said battery. It is left unhooked from the factory and is a very common question. Normally it gets answered sarcastically lol.
 

L79racer

Original poster
Member
Apr 26, 2012
13
Ray Dockrey said:
It is not needed. It is only needed if you are pulling a trailer that has its own battery. It provides the power to charge said battery. It is left unhooked from the factory and is a very common question. Normally it gets answered sarcastically lol.

Wow fast response!!! Thanks, I do tow an open car trailer, is that also to charge the emergency brake battery?
 

Black_tb

Member
Dec 6, 2011
817
just dont cut the red wire what ever u do :tongue::tongue::tongue::tongue:


lol sorry had to do it
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Here's where it goes. You need an M6 metric nut or wingnut. GM left it off (I think) because if they left it on, and somebody hooked up a large trailer with its own battery they were running a fridge on 12V, and it ran the trailer AND the vehicle battery down overnight because they were left hooked together, the owner could be stranded and cranky. Leaving it off like that makes the owner THINK about what they're doing, and what they SHOULD do is connect it by way of a high amp (30-50) solenoid that would disconnect when the ignition is turned off.

megafuse1-orig.jpg
 

David B.

Member
Dec 5, 2011
51
Ha! I've always wondered, this too. As well as my buddy at the office who has the same wire LOL. I love this forum...
 

Mark20

Member
Dec 6, 2011
1,630
the roadie said:
Here's where it goes. You need an M6 metric nut or wingnut. GM left it off (I think) because if they left it on, and somebody hooked up a large trailer with its own battery they were running a fridge on 12V, and it ran the trailer AND the vehicle battery down overnight because they were left hooked together, the owner could be stranded and cranky. Leaving it off like that makes the owner THINK about what they're doing, and what they SHOULD do is connect it by way of a high amp (30-50) solenoid that would disconnect when the ignition is turned off.

And a 12V camper fridge will kill a battery pretty quickly. Fortunately it was the camper's battery and not the tow vehicle.

I put the nut on both the Envoy and Silverado's 12V post (really like Roadie's wingnut idea) but left the wire disconnected with the intention of hooking up the wire only when needed. (Both have the same feature.) I have done so only once when I needed to top off the camper's battery. A 4.2L engine makes for an expensive generator!
 

Forum Statistics

Threads
23,272
Posts
637,481
Members
18,472
Latest member
MissCrutcher