How-To: Use SEO Connector of The MBEC for RAP GMT800.

rebelman06 · January 28, 2011

Mod: Using the SEO connector of the MBEC for Retained Accessories Power (RAP)

Years: Confirmed 2003-2007 Classic, possible for earlier GMT-800 models.

Cost: Should not exceed $20-25 (or much less depending on what is needed and shipping options)

Background:

The MBEC (located next to the brake pedal) contains the SEO connector that can be used to power added accessories. Inside of the SEO connector, which is located next to the trailer brake connector, is several 12V+ leads and 1 ground lead. There are two always hot leads, which are 30A and 15A. These two leads are good if you want to be able to run an accessory without key-on or for wiring in a relay with high-amp applications. The SEO Ign (10A) and SEO Acc (10A) are the leads that can be used for RAP, which means your device only gets power with the various key-on positions. I find the SEO Acc pin more useful, since I don't want my accessories powered up during the cranking cycle. The SEO Acc pin is active during Accessory and Run (after engine start) while the SEO Ign pin is active while the key is in the Start (crank) or Run position.

The following parts are needed:

-6 Pin Female Black Delphi Packard 280 series connector P/N 12193930 ($1.16 x 1 Available from http://www.mouser.com)

-Delphi Female 280 Series Automotive connectors P/N 15317768 (~16 gauge) ($.24 x 5 Available from http://www.mouser.com)

Additional p/n's for female pins can be found here: http://connectors.delphi.com/DCSGDMCS/DCS/...artNum=12193930

Website to convert MM to AWG: http://www.engineeringtoolbox.com/awg-wire-gauge-d_731.html

The following parts are optional:

-5 Pin SPDT relay and harness for high amp accessories

-heat shrink tubing or electrical tape

I recommend that you order an extra connector and several extra pins, since shipping will be the same and so you have extras to mess around with.

Steps:

Remove the round nut in the center and locate the tabs holding the cover on.

Release the second set of tabs and lift the MBEC out so you have more room to access it.

Here is a shot of the connector with the pins labeled according to my table below.

The table below shows what each pin can be used for. Before connecting an accessory to the Acc/Rap pin, make sure it will not exceed the amp rating. If it does, you will need to install a relay which can feed off of the SEO 1/2 pin or from the battery or under hood fuse block posts.

Reference shots of the connector and pins. (Note: The pins pictured are a slightly different part number. The ones listed above should lock in better than what I first purchased.)

If the accessory you plan to connect is going to draw more than 10A, you will need to purchase a 12V automotive relay as pictured below. The harness is not required, but they are not very expensive and make it safer/easier to remove or install the relay. For more information on wiring a relay, please visit http://www.the12volt.com/relays/relays.asp . The Acc pin would be the trigger, the SEO B1 or SEO B2 would be the 12+ supply, ground to ground, and finally the output pin of the relay to your accessory.

Even though I have checked and documented the pins for ground and 12V+, I highly recommend that you do the same before connecting any accessory to the MBEC in your truck. You can check the pins with a circuit tester (pictured below) or multi-meter set to 12V DC. I used both while investigating. You can check by confirming that the certain pins are always hot and that the others are hot only when the key is in the proper position. Checking will take just a few minutes, but could save your electronics if something is different on your particular model/year.

The following images are provided to inform you of where the SEO pins get their fused power from.

I have used this method to power my CB and it will eventually work as the RAP trigger for my upcoming sound system that will have an amp while using the factory radio. This setup would be good for powering a trigger for driving lights (powered by a relay in the engine bay), an aftermarket radio/screen that needs a little more power, amp remote turn on wire, ect. If you have any questions, please post in this topic and I can try to answer it or update my instructions to make them clearer.

BigBodySS · January 28, 2011

Great write-up, thank you so much for posting this. I have searched for more than a month and couldn't find anything that explained this anywhere near as clearly as you did.

I have one question: I am hooking up an AVH-P4200. I am not going to hook up an amp or subs or anything else to it. Will the deck draw enough to necessitate hooking up a relay or will it be fine as is?

Thanks!!

reiling3 · August 13, 2011

So, does this work with an aftermarket head unit? Does the factory stereo actually control the RAP function. I'm trying to use this method to keep my head unit on after the key is off. I'm not getting the 12+ RAP function anywhere in the MBEC. So I'm thinking I lost it when I pulled the factory stereo. I do have 12+ on pins 1 and 2 as shown in the OP's diagram, but that's only when the key is in the corresponding position. As soon as the key is turned off I lose power (no RAP function). And yes the doors where closed. Thanks for any help.

Ranger0001 · September 12, 2011

Mod: Using the SEO connector of the MBEC for Retained Accessories Power (RAP)
Years: Confirmed 2003-2007 Classic, possible for earlier GMT-800 models.

Cost: Should not exceed $20-25 (or much less depending on what is needed and shipping options)

Background:

The MBEC (located next to the brake pedal) contains the SEO connector that can be used to power added accessories. Inside of the SEO connector, which is located next to the trailer brake connector, is several 12V+ leads and 1 ground lead. There are two always hot leads, which are 30A and 15A. These two leads are good if you want to be able to run an accessory without key-on or for wiring in a relay with high-amp applications. The SEO Ign (10A) and SEO Acc (10A) are the leads that can be used for RAP, which means your device only gets power with the various key-on positions. I find the SEO Acc pin more useful, since I don't want my accessories powered up during the cranking cycle. The SEO Acc pin is active during Accessory and Run (after engine start) while the SEO Ign pin is active while the key is in the Start (crank) or Run position.

The following parts are needed:

-6 Pin Female Black Delphi Packard 280 series connector P/N 12193930 ($1.16 x 1 Available from http://www.mouser.com)

-Delphi Female 280 Series Automotive connectors P/N 15317768 (~16 gauge) ($.24 x 5 Available from http://www.mouser.com)

Additional p/n's for female pins can be found here: http://connectors.delphi.com/DCSGDMCS/DCS/...artNum=12193930

Website to convert MM to AWG: http://www.engineeringtoolbox.com/awg-wire-gauge-d_731.html

The following parts are optional:

-5 Pin SPDT relay and harness for high amp accessories

-heat shrink tubing or electrical tape

I recommend that you order an extra connector and several extra pins, since shipping will be the same and so you have extras to mess around with.

Steps:

Remove the round nut in the center and locate the tabs holding the cover on.

Release the second set of tabs and lift the MBEC out so you have more room to access it.

Here is a shot of the connector with the pins labeled according to my table below.

The table below shows what each pin can be used for. Before connecting an accessory to the Acc/Rap pin, make sure it will not exceed the amp rating. If it does, you will need to install a relay which can feed off of the SEO 1/2 pin or from the battery or under hood fuse block posts.

Reference shots of the connector and pins. (Note: The pins pictured are a slightly different part number. The ones listed above should lock in better than what I first purchased.)

If the accessory you plan to connect is going to draw more than 10A, you will need to purchase a 12V automotive relay as pictured below. The harness is not required, but they are not very expensive and make it safer/easier to remove or install the relay. For more information on wiring a relay, please visit http://www.the12volt.com/relays/relays.asp . The Acc pin would be the trigger, the SEO B1 or SEO B2 would be the 12+ supply, ground to ground, and finally the output pin of the relay to your accessory.

Even though I have checked and documented the pins for ground and 12V+, I highly recommend that you do the same before connecting any accessory to the MBEC in your truck. You can check the pins with a circuit tester (pictured below) or multi-meter set to 12V DC. I used both while investigating. You can check by confirming that the certain pins are always hot and that the others are hot only when the key is in the proper position. Checking will take just a few minutes, but could save your electronics if something is different on your particular model/year.

The following images are provided to inform you of where the SEO pins get their fused power from.

I have used this method to power my CB and it will eventually work as the RAP trigger for my upcoming sound system that will have an amp while using the factory radio. This setup would be good for powering a trigger for driving lights (powered by a relay in the engine bay), an aftermarket radio/screen that needs a little more power, amp remote turn on wire, ect. If you have any questions, please post in this topic and I can try to answer it or update my instructions to make them clearer.

I Have a 2007 GMC Sierra, everything looks the same as your describing here. When I check the connections in the SEO, i get the same readings before and after the RAP shuts down. I have not hooked anything up yet, I just need to understand better how is this going to work if the power never changes in the SEO. Did I mis read something? Do I need an additional component? Why dont I get a different reading on the 15 or 30 amp SEO B1 or B2?