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Posted

RAP aka Retained Accessory Power - powers on when the key is rotated to the first position and remains on until the ignition is turned completely off and the driver's door is opened (just like the factory radio)

 

If you look under the driver's side dash, between the brake pedal and parking brake, you'll see the fuse/relay box (it's about 6" x 10" and has a smooth black plastic cover, just like on the GMT-900's). Pry the clasps on each side to remove.

 

On my SLT there are three main banks, left to right, with the first being unoccupied (see attached pic). The slots within first bank are labeled 1-20, though only 11 actually have male connectors.

 

I used my tester to determine the following:

# 7 & 17 are constant 12v power [always on]

# 10 & 11 are grounds

#8 is the RAP [retained accessory power] ignition signal wire

 

 

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  • Thanks 1
Posted

There's a spade connector to RAP in the fues panel on the drivers side dash next to the door.

 

Its by the big blue wire connection in the side of the dash. Kinda tough to see in this pic.

 

I hate cutting into the factory harness.

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post-124606-0-65211300-1386704624_thumb.jpg

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post-124606-0-65211300-1386704624_thumb.jpg

  • Like 1
  • 2 months later...
Posted

 

RAP aka Retained Accessory Power - powers on when the key is rotated to the first position and remains on until the ignition is turned completely off and the driver's door is opened (just like the factory radio)

 

If you look under the driver's side dash, between the brake pedal and parking brake, you'll see the fuse/relay box (it's about 6" x 10" and has a smooth black plastic cover, just like on the GMT-900's). Pry the clasps on each side to remove.

 

On my SLT there are three main banks, left to right, with the first being unoccupied (see attached pic). The slots within first bank are labeled 1-20, though only 11 actually have male connectors.

 

I used my tester to determine the following:

# 7 & 17 are constant 12v power [always on]

# 10 & 11 are grounds

#8 is the RAP [retained accessory power] ignition signal wire

 

 

 

 

I just can't find the correct size spade connector to fit these. I even have the connector, part # 20791502 (was for my 2013) and never installed it because it did not come with these spade connectors.

Posted

 

I just can't find the correct size spade connector to fit these. I even have the connector, part # 20791502 (was for my 2013) and never installed it because it did not come with these spade connectors.

 

You can use these. I think they're 0.11" or a size similar to that..? Most of the national chain auto parts stores have them.

84541-007.jpg

 

Two things to add:

1) Make sure you cover them all the way to the tip with heatshrink or elec tape. The pins under dash are really close to each other & you don't want to pop a fuse by touching two at the same time.

2) Sometimes the tips on these are pre-crimped too tight. I like to use a small nail under each curved edge to loosen them a tad.

Posted

Anybody know if a connector is available that can be put in like the GMT900's??

I had my parts guy check, but with just the standard GM parts software he wasn't able to locate it (I know he's not BS'n me b/c it's the same guy that hooks me up with diagrams and part #'s all the time)

He did say the connector part number might be in some other service/tech doc that he didn't have access.. but he was able to give me the doc number (don't have them on me right now) and said a larger dealership might have access to it.

I didn't proceed b/c that's way too much effort for something solved with three cheap connectors. ha

Posted

Anybody know if a connector is available that can be put in like the GMT900's??

If you are talking about the RAP connector, part # 20791502 I can't say for sure but I do know for a fact it is the same for the 2013 model truck. I was able to pull that info from the web.

  • 1 month later...
Posted

Thanks for the tips, all. It has helped me complete my project. I installed a Homelink module. I'll search for a more appropriate thread to post results (or start a new one).

Posted

Anyone know if there is a way to access the RAP while staying the in engine compartment?

 

Also what is the real big difference between getting the GM connector part # 20791502 and just using a simple spade connector?

 

 

Sent from my iPhone using Tapatalk

Posted

Anyone know if there is a way to access the RAP while staying the in engine compartment?

 

Also what is the real big difference between getting the GM connector part # 20791502 and just using a simple spade connector?

 

 

Sent from my iPhone using Tapatalk

 

You can use spade connectors, I just prefer to use the connector

Posted

 

You can use spade connectors, I just prefer to use the connector

I understand that either can be used. I am just curious as to what the main difference is between the two options because I did not see much info as to what the GM connector looks like or anything about it.

 

 

Sent from my iPhone using Tapatalk

Posted

It really makes no difference, it is the OCD in me that wants the connector, it is just a square housing to hold the spade connectors, of which you would have to get special spade connectors to use the GM connector as that part number only has one wire with one spade connector included. I just prefer the factory look is all.

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