Finally got around to diagnosing what was causing or preventing the cdl icon on the dash from illuminating when the cdl is engaged. A bad transfer box switch. Was a bitch to access but I did it properly. Pulled the center console and drilled out the rivets to gain access to the top side of the transfer box. Was not sure which switch I needed to pull. As mentioned above there are what appears to be 2 identical switches beside eachother. I gambled on the switch closest to the nipple. The replacement switch part # IGM500011P. Seemed to do the trick. Had to adjust afew times though. If tightened too much the icon on the dash stays illuminated even when the cdl is not engaged. Does anyone know what the other identical switch is for? Not sure if it uses to same part # IGM500011P or what.

I also found a connector not plugged into anything. Again I'm not sure what its for. Was hoping someone could shed some light on it. Is it a blank? Is it suppose to be connected to something?







2 identical switches. I pulled the switch closest to the nipple mechanism. What is the other switch for?

Also found this white connector. Was not plugged into anything. What or where does it go?

Got the new switch installed, the plate back in place and new rivets installed. Cleaned up the area before reassembly.




Cdl icon now illuminates along with an audible chime when the cdl is engaged or disengaged. I happy.

 

As described in the RAVE on p.41-16, the 2004 truck has two CDL lock warning switches connected in parallel.
Not sure which white connector you are talking about.

 

As mollusc said, there are two switches so that when one fails the other will continue providing the ground path to illuminate the light in the instrument cluster. Changing either one would give you the light back but know that you still have a faulty one in there. Germans would require a better switch that would last 500k miles, the British decided they'd just give you two since they are crap and hope that one lasts, in an effort to delay the inevitable. Both of my CDL switches are bad as well (and the Hi/Lo switch) however I tapped into the large white connector shown just under the base of the screwdriver handle in your first pic and wired in a manual switch. Cumbersome at best, however I wasn't about to spend $150+ on crappy switches that take hours to swap out.

I was going to say that the other plug was likely the trans temp switch connectors, since most later trucks don't seem to have the temp switch however that connector is usually two loose spades and not a molded plug like the one in your pic. The only other connections there are the Hi/Lo switch and the Neutral detect. When you select Neutral on the transfer case, do you get a warning chime? If you select Low range, does your HDC function? If the answer to either question is no, then that's where it goes.

 

@TRIARII I think I have the same problem but not entirely sure. When your switches were bad did the CDL and neutral lights light up when turning on the ignition?

Mine don’t light up when in neutral or when the CDL is engaged but they also don’t light up with every other light when I turn on the key. So I’m not sure if the switch is the issue or the problem is deeper.

 

I can't recall off top of my head if the cdl or low range light illuminate on startup. But if you are shifting the cdl linking and engaging lock and no audio or symbol lights up on the dash then your best bet is to buy 2 new switches and replace them..

I replaced one of mt switches atop the transfer case. I was not awate during the job that there are 2 like minded switched for the cdl so I only replaced one.. But in doing so my cdl not triggers the symbol on the cluster and the audio. Be careful when installing new switches, not to tighten much. They are very sensitive and if you tighten them too much they won't work.