4x4 1999 Blazer switch problem

[Blazer_boy]

1999 chevy Blazer, v6, 80,000 miles, believe it's a 4.3L

2 years ago I had the 4x4 problem totally fixed for around $1700. Had to switch the transmission at least thats what they told me... I don't know tons about cars so slowly trying to learn more. Well my Blazer now has the same problem it did, but the switch isn't even lighting up when you switch to 4x4 mode, so I bought a new switch, this one isn't lighting up either, turns out the wiring might be the problem so will go look at that... has anyone else had high ammounts of problems with the 4x4 switch on the 99 blazers? Personally I'm not going to replace my transmission again for a while don't have the money and the Blazer runs fine in 2WD. I was just wondering if anything else besides the switch, wiring or transmission could be the problem, I dont think there really is but yea let me know. Like I said I'm still learning more about cars and trying.

thanks, DB

[MT-2500]

Originally Posted by Blazer_boy

1999 chevy Blazer, v6, 80,000 miles, believe it's a 4.3L

2 years ago I had the 4x4 problem totally fixed for around $1700. Had to switch the transmission at least thats what they told me... I don't know tons about cars so slowly trying to learn more. Well my Blazer now has the same problem it did, but the switch isn't even lighting up when you switch to 4x4 mode, so I bought a new switch, this one isn't lighting up either, turns out the wiring might be the problem so will go look at that... has anyone else had high ammounts of problems with the 4x4 switch on the 99 blazers? Personally I'm not going to replace my transmission again for a while don't have the money and the Blazer runs fine in 2WD. I was just wondering if anything else besides the switch, wiring or transmission could be the problem, I dont think there really is but yea let me know. Like I said I'm still learning more about cars and trying.

thanks, DB

Welcome to AF on your first post.
First as always check all fuses.
Is it just the 4x4 light that does not light up.
If so pull codes by grounding pin 13 on the diagnostic connector and tell us what lights light up or blink and how many blinks.
MT

[knowltg]

had the same problem trying disconnect the battery cable for like 15 mins and see if it resets it.

if it does it could be the tccm (transfercase control module) or the encoder motor. also put the truck in nuetral and see if you can goto 4 low if it goes you can try switching into 4hi if it still doesnt work. you are as far as i am wich is at the encoder motor. but so far mine is working after i disconected the batter for 15 mins.


mt2500, he has a 99 so it is an obd2 system. so he will not be able to jump it.

[MT-2500]

Originally Posted by knowltg

had the same problem trying disconnect the battery cable for like 15 mins and see if it resets it.

if it does it could be the tccm (transfercase control module) or the encoder motor. also put the truck in nuetral and see if you can goto 4 low if it goes you can try switching into 4hi if it still doesnt work. you are as far as i am wich is at the encoder motor. but so far mine is working after i disconected the batter for 15 mins.


mt2500, he has a 99 so it is an obd2 system. so he will not be able to jump it.

On a 99 OBD11 you jumper pin 13 to ground to get transfercase codes.
And on a 99 go easy on them battery disconnects or you might lose your air like the 200 blazer heat post.
Just pull your fuse to reset it.
MT

[knowltg]

can you do that with a 97, mt2500 that is jumper pin 13 to ground to get codes.

[MT-2500]

Originally Posted by knowltg

can you do that with a 97, mt2500 that is jumper pin 13 to ground to get codes.

Yes if it has the 233 electronic shift transfer case. [ push buttons ]
MT

[Blazer_boy]

Originally Posted by MT-2500

Welcome to AF on your first post.
First as always check all fuses.
Is it just the 4x4 light that does not light up.
If so pull codes by grounding pin 13 on the diagnostic connector and tell us what lights light up or blink and how many blinks.
MT

I'll do it... I still need a wire diagram but going to get that today... easy enough thanks for the response...

and I've already tried switching it to neutral and switching to low both don't work... the switch isn't the problem now because both 4hi and 4lo flash on start up now... But when i try to switch to them they don't light up... so could it still be a problem with the fuses? thanks

-DB-

[MT-2500]

Originally Posted by Blazer_boy

I'll do it... I still need a wire diagram but going to get that today... easy enough thanks for the response...

and I've already tried switching it to neutral and switching to low both don't work... the switch isn't the problem now because both 4hi and 4lo flash on start up now... But when i try to switch to them they don't light up... so could it still be a problem with the fuses? thanks

-DB-

One step at a time.
You need to get the code and post back code no or flashes.
They is only 4 different codes. 1 or 2 or 3 or 4.
MT

[Cruize]

This may be a dumb question, but when you press the button for 4 wheel drive, does the light for 2wd go out?

If so, the transfer case may be engaging the front end but not illuminating the light.

[tomcat826]

hi i have a 2000 blazer and 4x4 is inop- no lights on switch and nothing happens-i have checked fuses and changed switch still nothing-i have read alot of these forums and wondering if its the tccm. i was told that if their"s a code for 4x4 it needs to be cleared? we tried unhooking the battery for 30 min and nothing changed. i'm wondering if the code needs to be cleared first,service 4x4 light is on.. if you have any ideas let me know i don't want to just throw parts at it. thanx tomcat

[MT-2500]

Originally Posted by tomcat826

hi i have a 2000 blazer and 4x4 is inop- no lights on switch and nothing happens-i have checked fuses and changed switch still nothing-i have read alot of these forums and wondering if its the tccm. i was told that if their"s a code for 4x4 it needs to be cleared? we tried unhooking the battery for 30 min and nothing changed. i'm wondering if the code needs to be cleared first,service 4x4 light is on.. if you have any ideas let me know i don't want to just throw parts at it. thanx tomcat

Tomcat
On your problem you need to start your own post and give all info along with what transfer case you have and code no.
Hit the new thread button upper right corner.
MT

[tomcat826]

well its a 4 button so must be a 233 i am hearing alot about the tccm. i have power at switch but none at encoder motor. i just found out from on here that the ground wire runs with wiring for neutral safety switch? it seems to me it could be electical/wiring problem cause i hear nothing clicking and would explain no power to motor. i will keep trying to read what others say and if anyone has any info or anything that can help me out that would be cool. for a 2000 is the tccm behind the ashtray? i still need to jumper pin 13 not sure which one it is cause i have no schematic.

[MT-2500]

Start a new thread and someone will help.

[old_master]

Originally Posted by tomcat826

hi i have a 2000 blazer and 4x4 is inop- no lights on switch and nothing happens-i have checked fuses and changed switch still nothing-i have read alot of these forums and wondering if its the tccm. i was told that if their"s a code for 4x4 it needs to be cleared? we tried unhooking the battery for 30 min and nothing changed. i'm wondering if the code needs to be cleared first,service 4x4 light is on.. if you have any ideas let me know i don't want to just throw parts at it. thanx tomcat

Please start a new thread here: http://www.automotiveforums.com/vbul...wthread&f=2072