AUX switch install

[Willswilly]

OkK still Ned some help. I installed the upfitter switch.  All exciting switches work. AUX 1-4 light up when toggled.  I went to the junction box and located pins ,4,14, and 20.  I installed a fuse in slot 22 for upfitter switch 1 and I go nothing at the junction box. I tried both positive and negative with the test light on pin #1. What am I missing? Should I get some indication with a test light?

[TinkeringFox]

12 hours ago, Willswilly said:

OkK still Ned some help. I installed the upfitter switch.  All exciting switches work. AUX 1-4 light up when toggled.  I went to the junction box and located pins ,4,14, and 20.  I installed a fuse in slot 22 for upfitter switch 1 and I go nothing at the junction box. I tried both positive and negative with the test light on pin #1. What am I missing? Should I get some indication with a test light?

You likely don’t have the wiring between the switch (S48A) and the junction block (X61A) and are probably also missing the wiring between the X61A and the Underhood fuse box (X50A). You can easily bypass the X61A altogether and run 4 wires from the output pins on the S48A straight to the X50A passing through the firewall boot.

If you have the provisions for Upfitter relays (pins in the X50A) than you should be good to go after you connect the switch to the X50A.

[Penguin VII]

13 hours ago, TinkeringFox said:

You likely don’t have the wiring between the switch (S48A) and the junction block (X61A) and are probably also missing the wiring between the X61A and the Underhood fuse box (X50A). You can easily bypass the X61A altogether and run 4 wires from the output pins on the S48A straight to the X50A passing through the firewall boot.

If you have the provisions for Upfitter relays (pins in the X50A) than you should be good to go after you connect the switch to the X50A.

Are there directions for any of this? I've been reading through this, and am trying to figure it out although admittedly this is my first stab at anything like this. I seem to have the pins in the junction box, but beyond that I've got no idea what else there is to this, outside needing the new upfitter switches.

[captadamnj]

After reading through this thread numerous times, I put the following together to help me understand what was needed for a factory-like install on my 2019 3500HD.  Note that the Body Builder Manual referenced below MAY NOT APPLY TO YOUR VEHICLE.  However, many of the posts in this thread from owners of different 2014-2018 1500's and 2015-2019 HD's suggest the Aux switch circuits are nearly the same if not identical across these models and years.  The information is provided for USE AT YOUR OWN DISCRETION.

 

Wiring Schematic1,2
	Trigger		Trigger		Output		Output3
	S48A	X61A	X61A	X50A	X50A	X61A	X61A
Aux 14,5	X1 - 12	X5 - 10	X1 - 21	X3 - M5	X3 - M7	X1 - 16	X76 - 20
Aux 24,5	X1 - 13	X5 - 17	X1 - 34	X3 - F3	X4 - G2	X1 - 31	X76 - 14
Aux 34,5	X1 - 11	X5 - 11	X1 - 30	X4 - L6	X4 - K5	X1 - 35	X76 - 4
Aux 44,5	X1 - 10	X5 - 23	X1 - 38	X4 - L1	X4 - K2	X1 - 48	X76 - 1
Lead	13575783	19301767	19301767	19301767	19301761	19301761	13575832
1 See GM Upfitter Bulletin #110L, Figure 11
2 See GM Upfitter Body Builder Manual, 5-137-140, 5-170-171, 5-178-179, 5-654
3 See GM Upfitter Bulletin #115f
4 Trigger colors (Body Builder Manual) – Aux 1, RD/WH; Aux 2, YE/WH; Aux 3, GN/GY; Aux 4, WH/BU
5 Output colors (Body Builder Manual) – Aux 1, BU; Aux 2, GY/BK; Aux 3, L-YE/BN; Aux 4, RD/GN
6 Connector X7 needs to be purchased as part number 19328970 as per Bulletin 115f

 

 

A factory-like install can be accomplished by purchasing the GM "Leads", with the part numbers listed above.  One end of the wire will have a terminal that will go into the connector, the other end will be a pigtail that will be connected to the lead from the other connector, or may require you to lengthen the connection in order to reach the other Lead.  One advantage of the factory install is that you will have flexibility with how the switches operate as per Bulletin 110f by rearranging fuses in the X50A block. Note that the colors listed above are not the actual color of the leads, they are just what the colors the wires would be if the Aux switches were installed from the factory, and I note them here for easier reference when reading the pages listed in the Body Builder Manual; they are also noted in posts earlier in this thread.  Note that as per Bulletin 115f, the X61A junction block X7 connector will not be installed, you will need to purchase it as part number 19328970.

 

Here is an example build for Aux 1.  This assumes you have a switch panel and the correct X50A fuse block with factory relays and fuses. 

 

1)  Insert the terminal end of lead 13575783 in to the S48A switch connector X1 in position 12.

2)  Insert the terminal end of lead 19301767 in to the X61A junction block connector X5 in position 10.

3)  Route the above wires behind the dash and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 20 gauge wire so they do reach.

 

4)  Insert the terminal end of lead 19301767 in to the X61A junction block connector X1 in position 21.

5)  Insert the terminal end of lead 19301767 in to the X50A fuse block connector X3 in position M5.

6)  Route the above wires through the firewall and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 20 gauge wire so they do reach.

 

7)  Insert the terminal end of lead 19301761 in to the X50A fuse block connector X3 in position M7.

8)  Insert the terminal end of lead 19301761 in to the X61A junction block connector X1 in position 16.

9)  Route the above wires through the firewall and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 14 gauge wire so they do reach.

 

10)  Insert the terminal end of lead 13575832 in to the X61A junction block connector X7 in position 20. 

 

You now have output on a 30 amp circuit when Aux 1 is turned on.  You would repeat the above for the additional Aux switch circuits.

 

To try to tie together some other loose ends from this thread -

 

1)  If you don't want to pay the $$$ for the GM provided leads, TinkeringFox provided part numbers for the terminals themselves back on p.15; that info can be used to make your own leads/wires between the switch/junction block/fuse block.

 

2)  If you don't have the correct X50A fuse block, or want to create your own fuse block but use the switches, you can stop after step 1 above and then follow some of the posts for "making your own fuse box" in this thread.  The switches are then used as negative triggers on your own relays.

 

3)  If you have the correct X50A fuse block and you want power in the engine compartment instead of in the cab coming out of the X61A junction box, you can stop after step 7 above, and use the lead coming out of the X50A fuse block to power your loads.

3a)  Furthermore, as TinkeringFox pointed out, you can skip the X61A junction box completely.  In that case, you can skip steps 2, 3 and 4 and wire direct from the S48A X1 to the X50A.  For Aux 1, that would mean a connection from S48A X1 connector in position 12 directly to X50A X3 connector in position M5.

 

4)  There are at least 2 sellers on ebay that offer the X61A junction block X7 connector pre-wired and in various configurations.  I have no connection to these sellers, but they include dardz2015 and mcasnow.

 

5)  If you reconfigure your S48A switches, use the information posted elsewhere in this thread in conjunction with the referenced Body Builder Manual to determine the correct position to use in the S48A X1 connector.

 

 

Edited July 18, 2019 by captadamnj

[Fantastic]

31 minutes ago, captadamnj said:

After reading through this thread numerous times, I put the following together to help me understand what was needed for a factory-like install on my 2019 3500HD.  Note that the Body Builder Manual referenced below MAY NOT APPLY TO YOUR VEHICLE.  However, many of the posts in this thread from owners of different 2014-2018 1500's and 2015-2019 HD's suggest the Aux switch circuits are nearly the same if not identical across these models and years.  The information is provided for USE AT YOUR OWN DISCRETION.

 

Wiring Schematic1,2
	Trigger		Trigger		Output		Output3
	S48A	X61A	X61A	X50A	X50A	X61A	X61A
Aux 14,5	X1 - 12	X5 - 10	X1 - 21	X3 - M5	X3 - M7	X1 - 16	X76 - 20
Aux 24,5	X1 - 13	X5 - 17	X1 - 34	X3 - F3	X4 - G2	X1 - 31	X76 - 14
Aux 34,5	X1 - 11	X5 - 11	X1 - 30	X4 - L6	X4 - K5	X1 - 35	X76 - 4
Aux 44,5	X1 - 10	X5 - 23	X1 - 38	X4 - L1	X4 - K2	X1 - 48	X76 - 1
Lead	13575783	19301767	19301767	19301767	19301761	19301761	13575832
1 See GM Upfitter Bulletin #110L, Figure 11
2 See GM Upfitter Body Builder Manual, 5-137-140, 5-170-171, 5-178-179, 5-654
3 See GM Upfitter Bulletin #115f
4 Trigger colors (Body Builder Manual) – Aux 1, RD/WH; Aux 2, YE/WH; Aux 3, GN/GY; Aux 4, WH/BU
5 Output colors (Body Builder Manual) – Aux 1, BU; Aux 2, GY/BK; Aux 3, L-YE/BN; Aux 4, RD/GN
6 Connector X7 needs to be purchased as part number 19328970 as per Bulletin 115f

 

 

A factory-like install can be accomplished by purchasing the GM "Leads", with the part numbers listed above.  One end of the wire will have a terminal that will go into the connector, the other end will be a pigtail that will be connected to the lead from the other connector, or may require you to lengthen the connection in order to reach the other Lead.  One advantage of the factory install is that you will have flexibility with how the switches operate as per Bulletin 110f by rearranging fuses in the X50A block. Note that the colors listed above are not the actual color of the leads, they are just what the colors the wires would be if the Aux switches were installed from the factory, and I note them here for easier reference when reading the pages listed in the Body Builder Manual; they are also noted in posts earlier in this thread.  Note that as per Bulletin 115f, the X61A junction block X7 connector will not be installed, you will need to purchase it as part number 19328970.

 

Here is an example build for Aux 1.  This assumes you have a switch panel and the correct X50A fuse block with factory relays and fuses. 

 

1)  Insert the terminal end of lead 13575783 in to the S48A switch connector X1 in position 12.

2)  Insert the terminal end of lead 19301767 in to the X61A junction block connector X5 in position 10.

3)  Route the above wires behind the dash and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 20 gauge wire so they do reach.

 

4)  Insert the terminal end of lead 19301767 in to the X61A junction block connector X1 in position 21.

5)  Insert the terminal end of lead 19301767 in to the X50A fuse block connector X3 in position M5.

6)  Route the above wires through the firewall and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 20 gauge wire so they do reach.

 

7)  Insert the terminal end of lead 19301761 in to the X50A fuse block connector X3 in position M7.

8)  Insert the terminal end of lead 19301761 in to the X61A junction block connector X1 in position 16.

9)  Route the above wires through the firewall and connect the pigtail ends together with a butt splice or other connection method.  If the pigtails do not reach, lengthen one of the leads with 14 gauge wire so they do reach.

 

10)  Insert the terminal end of lead 13575832 in to the X61A junction block connector X7 in position 20. 

 

You now have output on a 30 amp circuit when Aux 1 is turned on.  You would repeat the above for the additional Aux switch circuits.

 

To try to tie together some other loose ends from this thread -

 

1)  If you don't want to pay the $$$ for the GM provided leads, TinkeringFox provided part numbers for the terminals themselves back on p.15; that info can be used to make your own leads/wires between the switch/junction block/fuse block.

2)  If you want power in the engine compartment instead of in the cab coming out of the X61A junction box, you can stop after step 7 above, and use the lead coming out of the X50A fuse block to power your loads.

3)  There are at least 2 sellers on ebay that offer the X61A junction block X7 connector pre-wired and in various configurations.  I have no connection to these sellers, but they include dardz2015 and mcasnow.

4)  If you don't have the correct X50A fuse block, or want to create your own fuse block but use the switches, you can stop after step 1 above and then follow some of the posts for "making your own fuse box" in this thread.

5)  If you reconfigure your S48A switches, use the information posted elsewhere in this thread in conjunction with the referenced Body Builder Manual to determine the correct position to use in the S48A X1 connector.

 

 

Ok so based on all of this since I do not have the relays in the X50 fuse box, if I add the S48A switches with the four aux switches they will have power I just have to pin pins 10-13 of X1 connector and run those to negative ends of relays? 

[captadamnj]

57 minutes ago, Fantastic said:

Ok so based on all of this since I do not have the relays in the X50 fuse box, if I add the S48A switches with the four aux switches they will have power I just have to pin pins 10-13 of X1 connector and run those to negative ends of relays? 

Yes, correct.  cfields and crazyjoker have some good posts on p.17 about how to use just the switches with your own relays.

[captadamnj]

Interested in using a switch with Hill Descent Control position as a momentary switch.  My truck does not have Hill Descent Control as a feature currently, but there are wires in positions 3 and 4 of my S48A X1 connector.  If I remove the wire from position 4 and tape it up, should I have any concern about that having impact on operation of the vehicle?  I would then insert a pigtail into position 4 and use that as momentary lead.

 

Also, for those that have opened up the guts of switches, is it possible to replace the Hill Descent Control switch from a TC/CL/HDC/Aux1/Aux2/Aux3/Aux4 panel with a blank switch from the TC/CL/Aux1/Aux2/Aux3/Aux4 panel and HAVE THE BLANK SWITCH NOT BE FIXED...i.e. have the same capabilities for triggering the momentary circuit but have the switch itself be unlabeled? 

[Fantastic]

Ok so my x1 connector looks like it already has a grey wire in slot 10 and a blue wire in slot 11? What does this mean for me if I’m trying to just bypass the x61 and x50? The only switches I have now are the TC and cargo light. 

 

 

**Edit** disregard I was reading the connector backwards lol

Edited July 20, 2019 by Fantastic

[captadamnj]

Yeah...one side reads left to right...the other right to left...

[captadamnj]

Answered my own question about using a blank stationary switch in place of a momentary switch.  The cover itself is what makes the switch stationary.  It is oversized on the back and on the bottom to limit movement.  I was, however, able to trim it down and make it work just like any other momentary switch.  Took me about a half hour with a file, go slow so you don't take too much material.  The bottom is pretty easy, the back takes a bit more patience to make sure you take off enough to allow full activation of the button without taking too much in which case you will loose contact with the button.

 

Here are the switches after removal...the stationary switch is on the right.  Both a view from the bottom and side are shown.  The yellow outline shows where to remove material, but it is pretty self evident.

 

 

 

 

 

And here is a side pic with the two switches after the material has been removed...hard to tell the difference!  (What was the fixed switch is now on the left and now functions identically to other one way momentary switches.)

 

 

Edited July 21, 2019 by captadamnj

[Fantastic]

On 12/30/2018 at 8:31 AM, TinkeringFox said:

Ok, let me get see what I have. Here is the bulletin about the diodes....

With this being said will I be facing the diode towards or away from the switch? If I’m reading the bulletin correctly the cathode is going towards the switch and the anode towards the relay?

[Willswilly]

There are 7 part numbers for the wiring leads. So if I want to use all four Aux switches I have to order a set of 7 for every switch and then a GM relay for the fuse panel. Correct???

 

Or call me 314-791-3249 

[Fantastic]

3 hours ago, Willswilly said:

There are 7 part numbers for the wiring leads. So if I want to use all four Aux switches I have to order a set of 7 for every switch and then a GM relay for the fuse panel. Correct???

 

Or call me 314-791-3249 

No you only need the cables that were mentioned earlier in the post. You add those to your pre existing connector and then wire those into a relay set up as switched ground.

[14silvrado]

Hi I bought the part with the traction cargo light and 4 aux switches for my 2014 silvrado 1500 wt this truck comes usually with the two button but I bought the 4 aux button one and I installed it where can I hook the wires from now or how can I find the wires that co trolled by these switches thr junction box pins are not controlled by these in my truck 

[muggzie202]

Might be late to the conversation but my 2018 Silverado 1500 did not come with the aux switch package. I reached out to Chevy to see if it is possible to install them. They said no the truck would have to come from the factory with them. Are they giving me the runaround or are they actually not possible to install?