Detroit DD16 GHG14 (2014-16) Fault Code: SPN 3031 FMI 19 (ACM) Diesel Exhaust Fluid Tank Temperature Signal Erratic via Controller Area Network

Posted by PerDiezel Solutions on April 27, 2026

NOTE: Please see the step by step troubleshooting procedures for this specific code.

NOTE: If the ACM (Computer module) has been programmed recently, clear code, test drive, and if code doesn’t come back releaes the vehicle.

PROBABLE CAUSES:
1. Check DEF tank header harness connector/wiring.
2. DEF CAN harness.
3. Failed DEF tank header.

WARNING!