4wd problem
 

Seems to be a problem with my 4WD, the Light on the panel does not stop flashing when engaged, any ideas what I should take a look at?

Welcome to the forum. It's customary to give us year and which 4WD system (typically either 3 button NP233 or 4-button NP236). But I can say that your 4WD system is telling you it's not engaging if the selector button is still flashing. The TCCM should eventually revert back to having the original selector button lit if it fails to shift. If it is a 4-button 4WD (with auto button) I recommend studying the following link - then ask further questions. https://blazerforum.com/forum/tech-a...rmation-41198/

A common problem is that the wiring connections at the TCCM get corroded. First thing to check.

If it is 3-button, they are a different animal - but TCCM connections are suspect on both systems.

Thanks!
I found some bad vacuum hoses and replaced them and the 4x4 started to work, exept the 4x4 lower that does not engage, I can hear a clonk but it switches back to 4 hi after a few seconds.
Any thoughts about that?
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Need to be rolling less than 5mph, with trans in neutral when you attempt to go in/out of 4-lo (at least mine does). This was per my 2001 owners manual.

Hm, but in stand still it should be working right?

Not sure what you mean by "in stand". The vehicle may need to be rolling slowly with transmission in neutral for the 4lo to engage/disengage. If you stop rolling, then the gears are no longer turning inside the transfer case. If it wont go into 4lo for any reason the light will stop flashing and will revert back to the last successful setting.

4 LO should also engage in standstill.

please read your owners manual regarding this.

It has nothing to do with handling im afraid, the 4wd lo does not engage ans switches back to whatever was engaged before.

2005 Dakota manual for NV233 electrically actuated reads:

4HI to 4LO or 4LO to 4HI
NOTE: When shifting into or out of 4LO some gear
noise may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
Shifting can be performed with the vehicle rolling 2-3
mph (3-5 km/h) or completely stopped.

The 1991 - 1994 with the electric NV233 with dash electrical switch are the same.

BTW:
Switching the HI-LO range should be accomplished only with the transmission in NEUTRAL.

TCCM will sense it and flash or do nothing.