Welcome. Can you see if the switch in the CAD is making full contact when engaged in 4x4? Test the switch wires at cad for voltage going in and out when engaged. If working well, maybe bulb.

 

Thank you for the reply! ill take a look today after work.

 

Have you confirmed the CAD hasn't been defeated? If the CAD is 100% locked all the time, the switch may never activate the light.

I would also verify the bulb...they do tend to burn out.

 

got in late last night, i will be checking today! how do you know if the CAD is locked all the time ??

 

Have to pull the cover and forks, see if someone pushed the collar over and put the top back on.

 

I replaced both the wire connector/harness and the CAD ball switch that goes into the TC. However, I bought a Dorman switch from oreilly's... possibly could be bunk ? I'll run the tests today.

 

If the bulb is good, it is likely the little switch on the cad where the wires attach or the wires, assuming the CAD is engaging fully in both directions. The wire should have power to one wire and send it to the bulb when engaged in 4x4. It could also be a vacuum leak where the cad works but does not hold fully engaged to hold the switch closed. Test switch/wires with a volt meter.

 

Cruise is activated by vacuum, with it not working you may have a leak there that is effecting the 4x4 indicator switch?
Wouldn't hurt to recheck all the vacuum lines to insure there are no cracked or broken off line connections in the entire system.

 

could I PM you about your gauges ? I want to get some installed and curious about how its done/labor cost if I pay someone.

 

I checked 90 degree connection at the cruise control servo under the batt tray and all looks well.

I did have a new development yesterday, I used the dash guage/lamp check using the trip odo and ignition and the 4wd lamp does not come on yet im getting power at the CAD switch. leads me to believe its a lamp behind the gauges.

as for the cruise control, since i already checked the vac lines and my AC and 4x4 are working, im assuming its a short in the steering wheel wiring or a clockspring issue... but thats for another time haha

 

would also like to add i think its the clockspring/steering wheel wiring bc i have an airbag light on...lol

The 3 gremlins i inherited with this truck: 4wd light, cruise control, and air bag light! one day ill fix them all... still troubleshooting and replacing little things.

 

You have a vacuum leak somewhere, It could be any line or quite possibly the diaphragm in the CAD. A small leak in the CAD will result in the diaphragm pulling the fork each way allowing 4x4 to work but it fall short of pulling it completely against the contact witch to turn the light on. That is the way my CAD failed. Also any line or elbow or joint can leak. Rubber fails and the hard lines will split, sometimes in invisible locations.

 

Okay, so you think I should double check the vac lines before i replace the gauge cluster light ?

 

Does your blower only blow on defrost?

 

everything AC/heat related works great

 

Do you have a hand vacuum tester for carburetors? A pistol grip that yo can pump up vacuum? I think they are about 40 bucks or less at Harbor Freight. If you had one you can test everything. That bulb costs 3 bucks for 2 of them , change it out it you like. I think your problem is a pinhole crack leak in the CAD diaphragm, or maybe a line. Different parts(actuators need different amounts of vacuum to work. Have you put a voltmeter on the CAD wire to the light when in 4x4 to see if it is both betting juice and sending it to the bulb? It is preferable to your wallet to do the testing I and others have suggested as opposed to parts replacement testing.

 

okay big fish ! I got a multimeter today and i have power at the switch AND when i use my finger to actuate the 4wd indicator "ball" switch, the light comes on the dash, so the dash bulb is OK.

Next i took off the CAD to check if the fork was moving OK, it moved 95% of the way left and right, but i think its not getting just that last little push to actuate the 4wd light.

Do you think my problem is the switch that the vac lines attach to, or the actual vacuum lines themselves ?

I do have a new vac pump and my AC works and the vac lines around the 4wd pass my visual inspection.

 

Another update… one of the 4 screws holding the cad housing to the front axle broke in half.

Just spent the last 3 hrs trying to extract with no luck.

Going to have my buddy come try an extractor bit or weld a new head on the bolt on Monday..

 

Try turning the screw with a dental pic. Worked for me on a u-joint bolt I broke off. I think you have a bad diaphragm in the actuator. If you have a vacuum tester (with pump) you could test it for sure. They are 75 bucks at Rock auto and twice that locally. Different systems, heater, cruise, CAD, etc may work with less vacuum than others.

 

got the broken bolt out! ordered a new 4wd actuator , coming in the mail tomorrow. will update after i install

 

for the record, LOTS of pb blaster and vice grips got the bolt out

 

Hell you had it easy, you had enough sticking out to grab a hold of.

 

Alright another update! 4wd dash light fixed! I installed a new diaphragm and 4wd switch on the CAD and it is fixed! very satisfying

Now im going to fix cruise control lol (no dash night comes on or nothin)

 

Good. My cruise light has not worked for a few years but cruise works fine. I don't care about that one so I have not tried to fix it so long as cruise itself works.

 

My cruise control light doesn’t come on and the buttons don’t do anything , and I also have an airbag light

My first check shows no continuity at steering wheel switches , so I’m going to replace the clock spring !

 

The air bag light is usually a bad clock spring in the steering wheel. Could be the cruise issue also. Have not checked today but recently Rockauto had one on closeout bu I think it was the wrong one for radio controls or something. Check it and look under the regular column.

 

I fixed air bag light AND cruise.... it was a bad clock spring! Thank you all for the help

Onto my next issue ... fuel pressure, i have gauges installed, i have 13 psi at idle and drops to 5psi at wide open throttle, occasionally 4psi...

I have 3/8" flex fuel lines and a fass 95gph but its old af, one of the old fass units where the filter is separate from the pump, red base on the pump... its probably 15 years old... maybe its going bad idk ill read some threads about it on here

 

Lift pump is getting weak if it drops that much, Check with another gauge first though.