GEN 2 Lighting and Aux/Upfitter Switch Questions

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NHnewbie

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Gen 2 Lighting and Aux/Upfitter Switch Questions

New 2018 SCrew owner here looking to install multiple BD lighting kits. I have spent much time searching for and reviewing posts here and on other sites on this topic, hoping to develop a sound plan for this install before I start turning wrenches and connecting wires. The BD install instructions make this task seem to be plug & play, however, the posts here indicate otherwise, with plenty of “gotchas” mentioned. I am highly experienced at electrical/electronics repairs and fabrication, but am a newbie when it comes to automotive wiring. So, I have some questions I haven’t found clear answers to so far:

1. The Raptor Owners Manual Supplement identifies six “Auxiliary Switches” which are described in many posts as “Upfitter Switches.” It goes on to state that these switches “control relays and fuses that are under the hood in the power distribution box.” I understand this to mean that there is already a relay and fuse installed for each of these six circuits, and as long as the load I connect to these circuits to is within the published current rating for a particular switch, there is no need for additional relays or fuses. Do I have this right?

2. The manual also mentions “pass through circuits.” I understand this to mean wires which can be used to bring the aux switch wire back into the cab if needed to control equipment installed in the cab. Since all the lights I plan to install are outside the cab, I am assuming I will not need these pass through circuits. Do I have this right?

3. I will be installing the standard BD Pro Fog Pocket kit and S8 Grille Bar kit up front. These installations seem fairly straightforward using the tips others have posted here.

4. I will install the standard BD S2 Reverse Light kit also. This is where things get a little muddy. Several posters here have recommended not tapping/splicing into the OEM backup light wire (as recommended by BD) due to the small wire size, but rather, to use a wire on the trailer connector to power the BD Reverse lights. In reviewing the various posts here there seems to be some difference of opinion about whether this works. In looking at the connections to the 7 pin round trailer connector, it looks like the center pin is for backup light power. What is unclear is whether or not power is applied to this connector pin when in reverse when nothing is plugged in to the trailer connector. If power is applied in this case, then tapping into the center pin wire with a Pos-i-Tap behind the 7 pin connector is an easy way to power the S2s. If a plug must be inserted into the connector to enable power, this isn’t going to work.

5. Others here advocate using the CURT 55384 patch cable to break out a connection to power the S2s, but other posts say this will cause the vehicle to see a trailer connected, causing other issues.

So, I’d like to get a clear understanding of all this before I dig in. The mechanical part of mounting the lights seems simple enough (except for the grille bar, which seems close to a heart transplant). The electrical part is more of a mystery, and I am hoping for some clear guidance from those who have done it successfully. Thanks in advance!
 
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grumble

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Gen 2 Lighting and Aux/Upfitter Switch Questions

New 2018 SCrew owner here looking to install multiple BD lighting kits. I have spent much time searching for and reviewing posts here and on other sites on this topic, hoping to develop a sound plan for this install before I start turning wrenches and connecting wires. The BD install instructions make this task seem to be plug & play, however, the posts here indicate otherwise, with plenty of “gotchas” mentioned. I am highly experienced at electrical/electronics repairs and fabrication, but am a newbie when it comes to automotive wiring. So, I have some questions I haven’t found clear answers to so far:

1. The Raptor Owners Manual Supplement identifies six “Auxiliary Switches” which are described in many posts as “Upfitter Switches.” It goes on to state that these switches “control relays and fuses that are under the hood in the power distribution box.” I understand this to mean that there is already a relay and fuse installed for each of these six circuits, and as long as the load I connect to these circuits to is within the published current rating for a particular switch, there is no need for additional relays or fuses. Do I have this right?

2. The manual also mentions “pass through circuits.” I understand this to mean wires which can be used to bring the aux switch wire back into the cab if needed to control equipment installed in the cab. Since all the lights I plan to install are outside the cab, I am assuming I will not need these pass through circuits. Do I have this right?

3. I will be installing the standard BD Pro Fog Pocket kit and S8 Grille Bar kit up front. These installations seem fairly straightforward using the tips others have posted here.

4. I will install the standard BD S2 Reverse Light kit also. This is where things get a little muddy. Several posters here have recommended not tapping/splicing into the OEM backup light wire (as recommended by BD) due to the small wire size, but rather, to use a wire on the trailer connector to power the BD Reverse lights. In reviewing the various posts here there seems to be some difference of opinion about whether this works. In looking at the connections to the 7 pin round trailer connector, it looks like the center pin is for backup light power. What is unclear is whether or not power is applied to this connector pin when in reverse when nothing is plugged in to the trailer connector. If power is applied in this case, then tapping into the center pin wire with a Pos-i-Tap behind the 7 pin connector is an easy way to power the S2s. If a plug must be inserted into the connector to enable power, this isn’t going to work.

5. Others here advocate using the CURT 55384 patch cable to break out a connection to power the S2s, but other posts say this will cause the vehicle to see a trailer connected, causing other issues.

So, I’d like to get a clear understanding of all this before I dig in. The mechanical part of mounting the lights seems simple enough (except for the grille bar, which seems close to a heart transplant). The electrical part is more of a mystery, and I am hoping for some clear guidance from those who have done it successfully. Thanks in advance!


  1. Yes you have this right - however beware that the owner's supplement on many of the 2018's is incorrect in showing which bundles go where - as well as the colors. On 2018's, the bundle closest to the fender contains the pass-thru wires and the bundle further inboard contains the hot wires. There are posts everywhere that show the CORRECT locations and colors.
  2. This is correct
  3. Yep
  4. If you're installing the Sports rather than the Pros (my suggestion), then just tap into your existing backup lights and be done with it. I can attest that it works just fine and they're not so bright as to blind everyone when you toss it in reverse. If you're offroading, you're going to want "real" spots back there anyway and that's going to take some wiring time.
  5. See #4
 
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NHnewbie

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grumble,

Thanks for taking time to answer my questions. From other posts here I have become aware that 2018 switch wire colors are incorrect in the manual and now have the correct colors. My biggest challenge at the moment is finding the switch wires. Nothing visible on a quick & dirty first look. The maximum extent of my offroading will be my gravel driveway, so the S2 Sports should be adequate. :biggrin:
 

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