So before I change out the vacuum switch; is it possible to have the vacuum hose lined upincorrectly to the switch? Would it do anything to rotate the hose and put it back on the switch?

 

So I just got done messing around with the 4wd a little more. I had my hand in between the vacuum actuator on the rusty spot of the cable like you said to do. I could manually move the cable back and forth, maybe about an inch. the bellows of the vacuum actuator was deflated, it felt like a balloon with no air in it. i kept my hand down there as my buddy pushed it into 4hi and nothing, you could hear the encoder motor engage the transfer case but I felt nothing up at the vacuum actuator. We tried this a couple more times and then my dash switch started blinking and it would no longer engage the encoder motor. The 4hi and 4lo lights would blink together 5 times. Is this a certain code?

I gave up on it after that and started to drive home. none of the lights were lit on the 4wd dash switch not even the 2hi light. Finally after about 5 minutes of driving the 2hi light came back on. What could be the cause of this? From what I read in another thread it sounds like this could be related to the vacuum switch on the xfer case.

What about the lack of air in the vacuum actuator, is this normal?

Again, appreciate all the input, this has been a big help for me.

 

Diagrams have been posted for the switch port designations, but just in case you don't do so well at searching...


To get the codes from the TCCM, you can follow the NV233 OBD2 diagnostic thread in the Tech Article (DIY) Index link found in my signature below.

So now you do not have vacuum to the actuator when in 4HI?? Your symptoms sound like they are changing...

 

Thanks for the link to the trouble codes. I will look into that.

As for the hose that connects to the vacuum switch, how do I identify which female ends on the hose match up with the male ends on the switch?

My symptoms wtih the 4wd are changing. I assume I did not have any vacuum to the actuator yesterday since the rubber bellows was soft and not full of air. It was my understanding that the light flashing 5 times meant a specific code. Using the OBD2 diagnostic thread it says I need to connect a jumper to diagnose. Isnt the flashing of the 4wd lights a code in itself?

 

That black rectangle corresponds to a protrusion on the switch that prohibits the plug from being put on incorrectly. The three vacuum lines go into the plug that then connects to the switch.

There isn't a '5' code in the NV233 TCCM... Only 1-4.

 

The 5 blinks was how many times the 4wd lights blinked after you would push 4hi to engage 4wd. I have not preformed the dtc yet by grounding the pin. All I do is ground pin 13 of the obd connection correct? I know for a fact that my encoder motor works because I heard it engage the other day and the motor itself was tested before it was put in the vehicle.

I will check for vacuum in the hose that goes to the transfer case switch again. I should feel vacuum out of one hose correct? Irregardless of if the switch is functional? A functioning switch would then send vacuum to the actuator correct?

 

Im have a similar problem... swart I have a 97 to can you briefly explain how to get the 4x4 codes 1-4 do I put a paper clip in pin #13 and #3 or what? I didnt really understand the other thread about it. THanks a lot! I think this well help both of us! oh and your k5 is a beast $500 is a steal!

 

From reading the OBD thread you have to physically ground it to something. So run a wire from that to bolt or something else not painted and bolted to the frame, like your alternator.

 

Yes, yes, and yes.

There is a link to the DLC pin layout/descriptions that will show you were there is a ground terminal in the DLC itself. From there, a paperclip can be opened up, bent appropriately, and used to ground pin 13.

 

Thanks I tried it and got nothing! If I had one stored would I have a CEL on?