420A Trouble codes and fixes

[Ariyal]

I have an issue with my 99 eclipse ha 420a. It’s throwing a p0700 and p0725 code. I’ve replaced both input and output sensors but the input speed sensor code came back. What else can fix this (car goes into limp mode after not shifting into 4th gear when reaching high speeds around 80mph) - new member

 

[97 eclenger]

Well, the p0700 means your tcm is bad, or has a short in it. I'd start by doing a tranny flush. Low fluid can cause issues and the tcm will pick up on it and set a code. Another common issue is actually the crank position sensor

 

[Ariyal]

Well, the p0700 means your tcm is bad, or has a short in it. I'd start by doing a tranny flush. Low fluid can cause issues and the tcm will pick up on it and set a code. Another common issue is actually the crank position sensor

Well, the p0700 means your tcm is bad, or has a short in it. I'd start by doing a tranny flush. Low fluid can cause issues and the tcm will pick up on it and set a code. Another common issue is actually the crank position sensor

 

[Ariyal]

The tranny fluid had been changed as well as the filter so it’s not that. But I’ve researched and saw that the crank position sensor could be a cause but was confused since it didn’t show and crank sensor codes. Is there a way to test the TCM or is my best bet just to buy one and change it along with the crank sensor?

 

[97 eclenger]

Id start with the crank sensor. If that does nothing then find someone with a tcm and test it that way