Note: Allpar does not take responsibility for the veracity of any information or opinions here, does not claim expertise, and is not responsible for any consequences. Please proceed at your own risk.




Chrysler ECU Computer Code 12

Code 12 is set when the battery has been disconnected and the computer (ECU) has been reset.  The power limited light will not light and limp mode does not apply. This code shows up when power to the computer has been interrupted as when the computer has been reset by disconnecting the battery.

Possible reasons for Code 12

Battery or power to the EUC disconnected – Code 12 is normal and doesn’t necessarily indicate a fault. If the battery has been disconnected or the electrical system has been worked on recently code 12 will indicate this. This code will is removed after about 15 engine starts.

Corroded Battery Terminals, Low Battery Voltage – Code 12 will be thrown if the system voltage drops too far below normal. This may be the result of a bad battery or the connection between the battery and the computer.  If the engine was jumped started and the battery terminals are bad and, this code may appear. 

Poor connection or bad wiring – Read the page ‘How to troubleshoot drivability issues’. Over time the pins in the connectors corrode/oxidize. Be sure to check the wiring and connections between the battery, power module, and logic module (or SMEC).  Fusible links from the battery should also be checked to be sure they are making good connection. 

Sensors, Switches, and Other Systems | Main Repairs Page | EEKs

This page is in-image-ad-free, 50% of the time. Support Allpar by using our Amazon link

We make no guarantees regarding validity, accuracy, or applicability of information, predictions, or advice. Please read the terms of use and privacy policy. Copyright © 1994-2000, David Zatz; copyright © 2001-2016, Allpar LLC (except as noted, and press/publicity materials); all rights reserved. Dodge, Jeep, Chrysler, Ram, and Mopar are trademarks of Fiat Chrysler Automobiles.


Exploring the 2018 Neon and C-100

CarPlay/A-Auto plans slip out

Building over the original Jeep plant

Survey: Allpar vs the world

All Mopar Car and Truck News


Challenger T/A and Charger Daytona  •  Jeep Dakar concept  •  2016 Classic Days at Schloss Dyck  •  Jeep Icon concept


2007 Chrysler Pacifica Dodge Stealth Chrysler in Spain The compact A-vans 1934 Chevy-Ford-Plymouth test