ERROR in my posted thread. This is for my 2012 Chrysler 300 S/B Chrysler 2012 300 Ltd, multiple issues

Hello All;
I have 2 issues that are ongoing. CEL and P0128 .
P0128 - Thermostat Rationality >Antifreeze level is good car heats up quick here in Minnesota winter.
so I am not thinking I have a Thermostat open/closed issue but am open minded for sure.
Temp gauge is slightly less than 1/2 way on the analog gauge.
Car has not been driven much, maybe 1000 - 3000 miles in the last three years.
Electrical - Currently, I have lost proximity features for door locks and trunk (FOB battery replaced 2 days ago 2/15/2025)
Remote Start Feature - This shuts off in less than 10 seconds, but I am assuming that the CEL being lit is responsible for that but again not sure.
I do not see reason to disconnect battery and then hope the Car Computer relearns everything on reconnect..

 

are you worried about the remote start or the check engine lite issue more?

 

W O W ....might even help if I put the right year in,,,IT;S A 2012, 73452 miles.
ok, now thay the right year of the car is in, I would say that the CEL is the most important.

 

you likely have a thermostat issue

 

CEL lamp will cancel remote start. Correcting the cause of the p0128 will cancel the CEL and allow the remote start to work as expected.

 

Thanks for the quick response's
I went and purchased the thermo/housing and will install today if possible.
Update to follow.

 

Eureka, Success,

After I replaced the thermostat, and driving a few days so the computer could re-learn things, the CEL has turned off, and remote start works again.
Coolant temp is running around 202-204 degrees F. Needle/Analog gauge is in the center of the dial between
Cold and Hot and heated up rather quickly than it did before.
Remote start was enabled from 40-50 feet away and I ran the motor for 10 minutes and never shut off on its own.

Thank You for the help CHRYSLER TECH and ggoose.