Dear all,

after a long time driving on a 2wd mode I was activating the 4wd mode.

The 4wd went in but after going back to 2wd mode the system got stuck on 4wd.

After a full stop I got lucky and it pulled back in 2wd. Now I am worried. I won't activated it again.

My car is located in Germany. There is not a lot of S10 here and no service at all.

How to start to do trouble shooting?

BR
Bob

 

Could be the vaccum lines that control the transfer case. Though Im not sure on our trucks if the TC is vaccum controled or not? Im sure someone will chime in with more experience with this

 

Thanks Cochran07

 

Is it push button?

 

Check out the Tech Article (DIY) section and see if any of the 4wd threads in there shed any light on the subject. If they do, please report back with what you found!

 

Dear all,
yesterday I received the new vacuum switch part no. 89059420.
When I removed the vacuum lines from the switch I could here the underpressure dissapearing.
Addtional water in the lines was dripping out.

With the original switch I was able to shift in 4wd high but not back into 2wd.
Now I replaced it with the new vacuum switch.
I realized now with the new switch that it won´t shift now in 4wd anymore. I disconneted the battery to reset the controller.
I tested on idle in newtral gear if I hear clicking from the transfer case while switch from 2wd to 4wd with the driver side door open.
Yes there is noise like a motor is moving something.

Would be the next step to check the vacuum actuator? Is it located under the battery?
How does it operate?

 

If it will not disengage, the problem is likely a sticking front axle actuator cable. It runs from the front axle up to the actuator that is located under the battery.

 

Thank you swartlkk,

how do I test the function of the vacuum actuator under the tray.

And how is it operated. I am looking for a electric vacuum actuator but can't find it. I am not seeing a actuator on the firewall?
Does the 97 Blazer has an actuator. I have the NV233 transfer case.

On the picture I greased the actuator. Hope it helps

How do you test the acuator.
Battery out, jump start and operating the 4wd switch?