2012 upfitter switches

[jdl8r]

Need help, so I'm attempting to revive this thread... I have a 2012 E350 with upfitter switches and I cannot for the life of me find the wires to connect to. Inside the engine bay there's a 4-pot of wires that connect to nothing that match wire-wise with the ones from the diagrams etc. however, when I use the upfitter switches there's no change? Anyhow, advice would be appreciated.

[dirtanddogfur]

I actually got the diagrams from my Ford dealer. I have them somewhere. They also tagged them in my engine compartment.



Let me see if I can track those down . . . . .

[jdl8r]

OOoh! That would be hugely beneficial... Thanks for looking.

[unreng]

although this is for 2009, try this - https://madocumentupload.marketingas...b5096&v5=False

https://fordbbas.com/vehicleModel/ESeries

[eddyturn]

For the upfitter switches, you will have to install relays into the master fuse box to allow the circuits to be used. I did not know that till my shop informed me of that.

[Flux]

Originally Posted by jdl8r

Need help, so I'm attempting to revive this thread... I have a 2012 E350 with upfitter switches and I cannot for the life of me find the wires to connect to. Inside the engine bay there's a 4-pot of wires that connect to nothing that match wire-wise with the ones from the diagrams etc. however, when I use the upfitter switches there's no change? Anyhow, advice would be appreciated.

Is there a wire harness inside the dash that is not connected? The one to the rear of the upfitters?


and what eddie said

[jdl8r]

Interesting. What's the purpose of the upfitters if we need to install relays for them to work? OEM looks I guess. What's interesting is that the switches illuminate, so they're drawing power from somewhere... I'll dig up the wires in the engine bay (all the other documentation showed them in the cab for F-series) and test em' with a volt meter.


Thanks all.

[dirtanddogfur]

Mine are already fused. If they are OEM, I believe that is the case.

[eddyturn]

Mine had fuses but there needs to be some relays (they told me) installed in the main fuse box. They were empty on mine and they put some in to make the switches work. The light on the switches worked but they did not operate anything until the relays. What I was told anyway.

[jdl8r]

Thanks again. That appears to align with what I'm seeing - no voltage from any of the wires. Anyone have details on the relays and their installation / specs?