I changed my battery today on my 2002 Blazer and now the lights are blinking on the 4X4 engagement buttons. Anyone ever experience this?

 

Need a lot more information from you...

Do you have the 3-button switch in the dash or the 4-button w/ auto4wd?

If you disconnect the battery for 10-15 minutes and reconnect it, does the 4wd system react normally?

 

3 button on the dashboard. I'll try disconnecting the battery for 15 minutes tomorrow and get back to you. Thanks for responding so fast...

Stu

 

Hey Stu, I just had a similar problem with mine. I disconnected the battery when I was changing the fuel filter and the 4WD wouldn't engage. The lights wouldn't even come on for me. I unplugged the battery for 15 minutes and then tried to engage 4hi. It then would light up and click, but immediately click back to 2hi. I did a little more reading and saw that you can reset a code that is stored in the TCCM by turning the ignition from on to off 5 times. Don't start it, just turn the key 5 times.

Problem solved! I hope this works for you.

edit: I found where I read about this. Scroll down to Chevy Lover's second post and you can read it for yourself.
https://blazerforum.com/m_38761/tm.htm

 

Thanks again everyone for all your help. It turned out that the problem resolved after I disconnected the battery for a while, probably something like a half hour or longer. [sm=headbang.gif] This is a great forum, I'm glad I found it.[sm=thanx.gif]

 

That likely will be a temporary fix. The TCCM disables shifts if a problem is detected. The fact is, a problem was detected. Resetting the TCCM caused it to forget and re-enable shifts. The problem will likely return. It could be today or it could be the time when you need the 4wd the most.

 

I never had a problem before, I only started when I changed batteries after my battery dying...

 

According to the thread I referenced up there with Chevy Lover, you should be good. The TCCM is storing a code because the RAM lost its standby power (changing the battery) and it automatically stores a code of 1.

Kyle knows his stuff, he is in pretty much every post that I have read on this forum. Here's to hoping that it is not just a temporary fix.

I agree, this forum rocks! There are a lot of helpful people on here and it has saved this beginner grease monkey a lot of time and effort. It is going to be tough to contribute anything that can't been done by these guys/gals. I am only regurgitating this info, but if I can save an hour of reading for someone, I am glad to help.

 

A code of 1 should not prohibit the shift functions, but weirder things have happened.