CAT 3406E (Prefix 1MM or 2WS) Fault Code: 12 PID: SPN: 111 FMI: 4 Coolant Level voltage low
The Engine Control Module (ECM) detects the following conditions:
•The signal voltage from the coolant level sensor is greater than 4.5 VDC for more than ten seconds.
•The “Coolant Level Sensor” parameter is programmed to “2-wire Float Sensor”.
•The ECM has been powered for at least two seconds.
Probable Causes:
1) Coolant Level Sensor
2) Coolant Level sensor wiring
3) ECM failure
![International Truck ISIS - Oncommand Service Information Q4.2020 [04.2020]](https://www.ecuforcetruck.com/wp-content/uploads/2022/01/OnCommand-2020-1-300x300.png)
