4WD problem

1997 Blazer 4WD is not working. When you push the buttons to change to 4 high you can hear a slight change but it doesn't engage.

We have replaced the switch on the transfer case and the actuater located underneath the battery tray.

Any ideas on what may be causing the problem?

Does the transfer case shift to 4W high and 4W low?
Does the front axel lock in?
Does the shift buttons indicate a shift?

Yes, the transfer case is shifting to 4 Hi and Low. The buttons are functioning normally....they don't blink or change back to 2WD in its own. We checked the vacuum lines this morning and they are all fine. My husband says "there's nothing happening in the front end".

Any ideas?

Yes, the transfer case is shifting to 4 Hi and Low. The buttons are functioning normally....they don't blink or change back to 2WD in its own. We checked the vacuum lines this morning and they are all fine. My husband says "there's nothing happening in the front end".

Any ideas?

Is the actuator getting vacuum from transfer case vacuum switch?
Can you manually pull the actuator cable and lock in front axel?
Can you hear actuator solenoid work or is vacuum making it way threw it?
This link may help.
http://www.automotiveforums.com/vbulletin/showthread.php?t=572914
MT

The actuator is getting vacuum from transfer case vacuum switch.
No I cannot manually pull the actuator cable and lock in front axel.
Yes I can hear the actuator solenoid working.

When I pulled the triple vacuum hose fitting away from the switch on top of the transfer case to change it there was a lot of vacuum. The ball-shaped plasitic resivoir attached to the hood has vacuum when you disconnect the line.

Could I simply have a seized cable?

The actuator is getting vacuum from transfer case vacuum switch.
No I cannot manually pull the actuator cable and lock in front axel.
Yes I can hear the actuator solenoid working.

When I pulled the triple vacuum hose fitting away from the switch on top of the transfer case to change it there was a lot of vacuum. The ball-shaped plasitic resivoir attached to the hood has vacuum when you disconnect the line.

Could I simply have a seized cable?

Yes could be or someting in front axel.
I would remove cabel and see if it is stuck.
MT