Anyone know why a 99 Chevy blazer would engage 4-Hi 4wd but not 4-Low?

2-Hi and 4-Hi work just fine but the 4-low just won't engage. Trying to figure out if  can DIY fix it if it's something simple, rather than pay an exorbitant amount to a mechanic. Thanks.

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red9er6 years ago
since it's a push button to engage the 4WDlow, there might be a corroded connection or wire... have have u ever spilled pop or coffee on the button? Also check the connection from the power to the switch, and then to wherever it goes after that... do you have a multimeter or test light? I wouldn't know if it uses a separate fuse and like kylara70 said, it might be a relay not making contact.
jj.inc6 years ago
The two things are completely different in your transfer case or transmission, just so you know not to think of it as being linked. This means your problem is the switch between Hi and Low, take it to a repair place, it is either electrical or mechanical so if the mechanic says it is electrical then you can probably DIY otherwise, if it is mechanical, you probably can't or else you wouldn't be asking.
tireswing6 years ago
Potentially you may have wonky electrical problems as my 98 has developed. I've disconnected the battery more than once to try to "reboot" and it seems to have helped in at least two instances. Once was when I couldn't get it _out_ of 4WLO. Best of luck to you. I'm soon taking mine to an auto electrical shop.........bummer.
kylara707 years ago
4-low is a gear shift, rather than a clutch change. So when you push the button there is a solenoid that may not be working. For 2-hi and 4-hi it is a clutch change.

Have the error codes pulled from the cars computer and you will likely find the problem.

DIY: get chilton's manual. find the shift solenoid and trace the voltage.
seandogue7 years ago
Can't say for sure with the 99, but I used to own a 91, and it took a bit of effort to engage the 4-Low setting. As I recall, you could not shift into low on the fly, so the question I'd ask is are you trying to do that or from a full stop?
A.J.B. (author)  seandogue7 years ago
Trying at a full stop in neutral, but for whatever reason it just won't engage. It is the push button style too if that helps.
idrawupay7 years ago
Did you put it in neutral first?
I think it only engages when the transmission is in Neutral.
Re-design7 years ago
You might be able to adjust the shifter. It it's an electric shifter the there is even a better chance that that's it.
kill-a-watt7 years ago
NP208, NP205, what do you got? I don't even remember what came stock anymore.