Trans over temp.2007 CRD - Jeep Garage - Jeep Forum

Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WK > Troubleshooting/Problems

Join Jeep Garage Today
Thread Tools Display Modes
Old 10-17-2013, 04:14 PM
roddaz's Avatar
My Jeep: 2007 3.0L WK
Join Date: Apr 2010
Location: Newcastle upon Tyne United Kingdom
Posts: 323
Thanks: 0
Thanked 5 Times in 5 Posts
Rep Power: 2856
roddaz is on a distinguished road
Trans over temp.2007 CRD

Tonight driving home, 5 minute journey got the eng management light flashing and limp home mode. When cycling the ign key I get Transmission over temp but only for a second.
Are these problems connected ?
Any ideas??

Present :2007 Grand Cherokee CRD.Fiat 500 lounge.
Previous:1997 XJ Turbo Diesel,1999 Mustang V8 GT Conv.1979 CJ7,1975 CJ5,Fiat 500 street.
Reply With Quote
Sponsored Links
Old 10-26-2013, 02:28 AM
New Member
My Jeep: 2006 5.7L WK
Join Date: Jun 2012
Location: Southeast USA
Posts: 4
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
06_Hemi_Overland is on a distinguished road
Re: Trans over temp.2007 CRD

Originally Posted by roddaz View Post
Tonight driving home, 5 minute journey got the eng management light flashing and limp home mode. When cycling the ign key I get Transmission over temp but only for a second.
Are these problems connected ?
Any ideas??
This is such a common problem for these vehicles. Here is my take. I have an 06 Overland with 5.7L 4WD. I know it isn't the diesel. I have been chasing the same problem for about a month now.

First thing I started with was the solenoid pack in the trans above the valve body. I've learned that on my vehicle it has a 545RFE Trans which is built by Chrysler. The other trans is the NAG1. NAG stands for New Automatic Gearbox. The trans temp in the NAG1 is part of the governor. It's easier to replace. I had a temporary relief from this trans overtemp issue for about 2 days and it came back. After checking the wires up top at the PCM and at the top of the trans I concluded the wires and connectors were fine. Also checked Ground wires and Positive cables.

Using a LAUNCH CRP 123 scanner I went into the data stream menu under the trans module to monitor voltage of the temp sensor and Temp reading. Driving in traffic, highway speeds and idle. The voltage reading would be steady at 3.xx V and all of the sudden just drop to 0.50 V. When it dropped out the temp went from a normal 170 ish to over 300 in a matter of a second. That is not physically possible for the fluid to change temp that fast.Light back on for Trans Overtemp. That told me that it was related to the temp sensor. In my case the 545RFE has the trans temp sensor included in the solenoid pack. Getting back to what I ultimately did, I replaced the PCM. I used a company called AutoComputer Exchange in Davie, Florida. $169.17 w/ free shipping. Just mail them back your core and you get a one year warranty.

I installed that today and everything worked out until I had to figure out how to perform the re-learn procedure for the TPS. I had the red lightning bolt on the dash. Now everything is solid and I'm hoping for the best. Now the voltage range is more stable and the temp readings are normal. Hope this helps!

There is not enough info on how to combat this issue out there! I have also read that the commander has a no start condition with this issue. They have had better luck by replacing the starter. When the Trans selector is in Park or Neutral it supplies a ground. The starter is on the same circuit. Make sure you find out which transmission you have before proceeding.
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
trans says over temp dippinsoldier92 Troubleshooting/Problems Discussion 0 07-11-2013 06:37 PM
Trans Over Temp Blinking grand07cherokee Troubleshooting/Problems 9 01-27-2013 04:48 PM
Trans Temp Gauge linenfelserrogdr Engine Performance/Intake/Exhaust 6 06-28-2012 08:26 AM
Trans Temp Gauge linenfelserrogdr Tech Tips/DIY/How to 5 06-20-2012 06:38 PM
Safe trans temp ekaz Performance Modifications 3 08-05-2011 09:21 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 07:57 PM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community is in no way associated with or endorsed by FCA US LLC. Chrysler, Dodge, Jeep, Ram, Mopar and SRT are registered trademarks of FCA US LLC.