Hi XXXXX. Thank you for asking your question on JustAnswer. There is an actuator on the transfer case and another pn the front differential.It is common for these to go bad. Start with the one on the front diff, have someone put it in 4wd will you tap it with a hammer. Let me know what happens
Jason
Is this just a push button 4wd? Do you know if it has A.D.D
It's the A.D.D. There is no push button. I was looking in the book and it shows a relay for the ADD but doesnt say where its at. Kind of looks like it on the drivers side fire wall but can't find it.
Thanks
Ok. There are quite a few parts that may be the issue, the most common is... There is a 4wd position switch located toward the top of the transfer case (drivers side) It has a 2 pin connector. This tells the ecu that you switched the transfer case into 4wd,and to apply power to the vacuum switching valve, then the vacuum engages the front diff actuator.
Once you find it, unplug it and jump the 2 pins with a wire or paper clip. Then retest the 4wd... Let me know
Do they both have plugs, or does one have a wire?
I shorted out the blue one nothing happens?
No it was the valve towards the front of the vehicle. Do you want me to try other one?
I have also checked out the ADD solensoids and they seem to be OK. Both have a OHM reading of 40 and when power is applied air flows from the filter side out the dischage side of the valve.
You need to apply vacuum to the front diff actuator, this will test to see of its working.
The actuator is sticking, and you moved it with the vacuum. If its a customers car, I would replace the actuator. I was gonna say the actuator from the start, but wanted to go through the diag to be sure. it'll work for now, but will malfunction again.
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