4X4 dash switch intermittent.

[BC99]

Hello guys, I have an appeal to all of your collective experience. I have an issue with my '99 K2500 (cross-over year truck. Think '98 GMT400). The 4 wheel drive switch only works when it feels like it. Often there are no lights at all. Sometimes it won't even operate the 4-wheel drive. Sometimes everything works and all of the applicable lights work correctly. I have a general knowledge of the components of this system. Just wondering if any of you out there have seen this and can suggest which component is on the blink? This past winter I notices this. It usually operated after a couple of tries but the lights wouldn't stay lit. Yesterday at a sandy river beach I was thinking of using 4 high as a precaution to not get stuck and I couldn't get anything. I was 2 hours from home and when I tried at home the transfer case engaged into all three ratios but the lights wouldn't stay on. is this the dash switch?

 

[Cadillac Bob]

So it’s just the switch back in 99 my dad bought brand new LS burban 4x4 with auto 4x4 the lights never really light all the time! Mine only really light in morning when cooler outside lol but everything works as it should and you should feel the difference in front end when it’s engaged!!! But it’s just one of the many qwerks of the 400 line up! Lol no need to buy a new switch possibly put bulb grease but unless your 4x4 isn’t working it’s just a qwerk!!!

 

[BC99]

Thanks very much. I was assuming that the switch was the issue but the last 4x4 I owned shifted manually so I hadn't explored the electrics much. I'm glad once I did I found out the systems are pretty simple. It was a bit worrisome yesterday driving on sand with the heavy vintage camper (shown in my profile) onboard and no 4 wheel drive as insurance. Then it worked when I got home!
... and yes, once home, the front axle definitely engaged and I could feel the front wheels working. I'll clean and grease that switch.

 

[Macs Garage]

Mine engages and disengages but the lights don't always work. I press on the switch harder or dash around it and lights will come on for a little while. I took the switch out hoping to see a bad ground or something amiss, but it is sealed.

 

[BC99]

Thanks. Puts my mind at ease. The lights seemed to work all of the time when I first got this truck but not so much now. One other member suggested dialectic (bulb) grease to improve the contacts in the plug. I may try that. Not that the lights are that important. It's pretty difficult not to know when your truck is in four wheel drive.

 

[east302]

Like Macs Garage, I had one where the lights would work if you pressed hard on the corners of the switch (not the buttons). I opened up the switch and re-soldered some cracked joints. Been working fine since then.

 

[deadbeat]

Mine did the same thing, you could push around and hold when the light came on and it would switch. I tried dielectric grease and it didn't help, finally just put a new switch in and it works great now for the last 6 months or so.

 

[deadbeat]

And, I just opened up my old one and see cracks in the solder where the pins go down for the plug, likely all that was wrong with it as @east302 said.

 

[BC99]

I see online that these switches are not expensive at all and I've had the dash off before and it's surprisingly easy in these trucks. I might just replace the thing. An hour of my time a less than $50 seems worth it.