PCM transmission problem

Tony Ownbey

Tony Ownbey

3 - DAWG
Supporting Member
Joined
Nov 26, 2017
Messages
26
Location
Eugene, OR, United States
I have 2006 Unlimited Rubicon with an a/t. Recently it started to shift awkwardly from first to second. I went with a good cleaning and fluid change. My A/T guy said he was reading two codes related to transmission temperature. He indicated I needed a new computer and he was only finding new ECM/PCM in the area of $700-$1200 with them taking 2-3 weeks to refurbish my unit. I reviewed this forum and others for some knowledge. I did get the price down to nearer $400 but read where one person suggested disconnecting the battery, thus allowing the ECM to do a restart. I thought a 5 minute repair was unlikely but worth a shot. So it's been a week now and my transmission is shifting perfectly. I'm holding my breath that the codes will return and the bad shifting but so far, so good.
I just thought I might pass this on and reaffirm all the good tips on this forum. I appreciate all these TJ gurus that offer up their knowledge .
 
  • Like
Reactions: Alex1985, jgaz, KCsTJ and 1 other person
That has to be a big relief! Unhook the negative battery cable for 5 minutes or so and boom. Tranny is fixed. I hope it stays fixed for u. Thats a wonderful transmission story. :)

I just paid a local tranny franchise (BIG MISTAKE i know now) over $1500 to put their greasy paws on my jeep and they kept it a month.
You dont want a tranny shop touching your jeep imho. :)
 
Glad you tried the battery method first. This is something most people forget to do, so I'm glad it worked out for you!

Now just think of what you can do with that money instead!

Oh, and welcome from Salem, Oregon!
 
I actually just bought some bartact seat covers since I saved on a transmission repair. Flawed logic but oh well. My wife went for it so it must make good financial sense? My wife is rarely wrong after all :0)
Chris said:
Glad you tried the battery method first. This is something most people forget to do, so I'm glad it worked out for you!

Now just think of what you can do with that money instead!

Oh, and welcome from Salem, Oregon!
Click to expand...
KCsTJ said:
That has to be a big relief! Unhook the negative battery cable for 5 minutes or so and boom. Tranny is fixed. I hope it stays fixed for u. Thats a wonderful transmission story. :)

I just paid a local tranny franchise (BIG MISTAKE i know now) over $1500 to put their greasy paws on my jeep and they kept it a month.
You dont want a tranny shop touching your jeep imho. :)
Click to expand...

I’m lucky it seems to have worked out. I do have an honest transmission shop I’ve used for years. I went to them with another tranny problem a couple of years ago. We drove around with his computer and he fixed a shift problem. He informed me then that anytime your voltage goes below a certain point (12.3 v?) it can mess with your computer and it has to be reset. I thought I was buying a trans. Rebuild then but he sent me on my way, no charge . He asked me if I had recently jump started another vehicle and bingo I had. They told me also that even not having enough coolant can affect a/t shift changes , which i’m Still not sure I understand, unless it’s a temperature thing. I got the lecture on being careful on jump starts. I now carry a portable jump starter. It’s great! One more thing I can’t live without. ;0)
 
  • Like
Reactions: Chris and KCsTJ
Yes sir, this has worked so far for me as well.
I’ve reset my PCM twice in the three+ years (approx 12K total miles) since I’ve owned my 06 LJ. It’s been fine for about 15 months now. (Knocking On Wood while typing)

My RPMs were winding way too high in 1st gear and shifting really hard into second.
 
With my transmission it was as if it went from second to first and back to second gear? For an instant it was like someone put the brakes on. After a mile or two the problem would disappear. This sounds like the same problem you had. I'll be very happy if I can do this reset every year of so. With all the reading I've done it seems like I should find a back up unit as a core if nothing else. In my experience, that way my A/T will run perfect and I'll never need it. I have a garage full of parts I'll never need but it makes me feel better.
 
following up - how is the jeep running? any issues later on? dealing with same issues you both have discussed. In regards to resetting PCM - are you just resetting battery or are you doing the disconnect negative and ground, reconnect, turn car on, flash light off and on reset PCM method?
If its still working well- did you do anything special while it was in "learn mode" such as driving slower or letting car idle a bit longer anything?
Keep me updated thanks!
 
Tony Ownbey said:
With my transmission it was as if it went from second to first and back to second gear? For an instant it was like someone put the brakes on. After a mile or two the problem would disappear. This sounds like the same problem you had. I'll be very happy if I can do this reset every year of so. With all the reading I've done it seems like I should find a back up unit as a core if nothing else. In my experience, that way my A/T will run perfect and I'll never need it. I have a garage full of parts I'll never need but it makes me feel better.
Click to expand...
 
jgaz said:
Yes sir, this has worked so far for me as well.
I’ve reset my PCM twice in the three+ years (approx 12K total miles) since I’ve owned my 06 LJ. It’s been fine for about 15 months now. (Knocking On Wood while typing)

My RPMs were winding way too high in 1st gear and shifting really hard into second.
Click to expand...

Am considering purchasing LJ - do you have an update?
 
Top Bottom
Back