Electronic Control System Signature, ISX and QSX15 Engines – FAULT CODE 441

Unswitched Battery Supply Circuit


Fault Code: 441
PID: P168
SPN: 168
FMI: 1/18
LAMP: Yellow

Battery voltage below normal operating level.

Possible no noticeable performance effects or possible rough idle.

Unswitched Battery Supply Circuit

Circuit Description

The electronic control module (ECM) receives unswitched battery input through the OEM harness. There are two in-line 15-amp fuses in the unswitched battery wire of the OEM harness to protect the engine harness from overheating. The battery return wires are connected directly to the negative (-)
battery post.

Component Location

The ECM is connected to the battery by the OEM harness. This direct link provides a constant power supply for the ECM. Use the OEM troubleshooting and repair manual for the battery location.

Shop Talk

Make sure the ECM unswitched battery supply is coming directly from the battery and not the starter.

Refer to Troubleshooting Fault Code t05-441.

Last Modified:  26-Oct-2010