Nothing but 2wd

[dedeisel]

So tooling around on my 05 Trailblazer this weekend i found out the hard way that my 4wd don't work in fact AWD,4HI and 4LO dont work the selector lights on the switch are moving fine but it just stays in 2wd but after messing with it for awhile it did finally work one time to get me out of the mess i got into
any ideas?

Thanks

[maxwedge]

Many things can cause this, the dash switches were problematic and on 2002-2004, the transfer case encoder was also an issue.

[dedeisel]

Everything seems to be functioning other than the actuator on the front diff seems as if though its not pushing all the way in

[maxwedge]

Is the ft driveshaft driving the ft diff but the axles are not locked?

[dedeisel]

Yes the drive shaft is turning into the diff but it's not locking. If I take the actuator out of the diff and push the plunger in it locks no prob, so i dunno if it's a actuator prob or a calibration prob?

Derek

[maxwedge]

Could be the actuator or even the transfer case encoder which was a more common issue. For a proper diagnosis a factory manual should be used for troubleshooting.

[dedeisel]

Originally Posted by maxwedge

Could be the actuator or even the transfer case encoder which was a more common issue. For a proper diagnosis a factory manual should be used for troubleshooting.

Got a hookup for one by chance?

[scotamore]

whats tran case encoder? thanks

[scotamore]

whats tran case encoder? thanks

[maxwedge]

Ok, the transfer case encoder is the device on the transfer case that engages the front driveshaft and selects 4h, and 4l as well as 2h. It is electronically controlled.