Code Details
| Display code | Navistar Aware SPN 841 FMI 12 |
|---|---|
| SPN | 841 |
| FMI | 12 |
| OEM code | Navistar / International Aware SPN 841 FMI 12 |
| Manufacturer | Navistar / International |
| System | Aware Vehicle Intelligence / Telematics |
| Component | GPS module — device failure |
| Source address | Unknown or not applicable |
| Severity | medium |
| Review status | ai source checked |
| Source confidence | high |
| Last reviewed | 2026-03-26 |
Plain-English Meaning
This is a hardware fault in the GPS function itself, not a coverage issue. FMI 12 means the Aware module detected that the GPS component is not responding or has reported an internal failure — distinct from simply not having satellite signal (which would be FMI 2). The GPS function of the Aware module is not operating and will not recover without hardware attention.
Navistar S08312 maps Navistar Aware SPN 841 FMI 12 to GPS Module — bad intelligent device or component. The fault sets when the Aware microprocessor cannot communicate with the GPS device, or when the GPS device indicates a failure condition to the microprocessor.
Common Symptoms
- GPS position is permanently unavailable in the fleet portal — not intermittent or coverage-related
- Fault does not clear when the vehicle moves to an open outdoor location
- Navistar diagnostic software shows the GPS module as non-communicating or in failure state
Possible Causes
Possible causes may include the items below. The list is not a parts diagnosis.
- GPS module or the Aware module's internal GPS component has failed
- GPS antenna cable open, shorted, or terminated incorrectly at the module — loss of the antenna connection can cause a GPS device fault
- Moisture ingress or damage to the Aware module affecting the GPS circuitry
First Checks
- Confirm the fault does not clear in open outdoor conditions — this rules out a simple coverage issue and confirms a hardware concern.
- Inspect the GPS antenna cable and connector at the Aware module for damage, loose connection, or corrosion.
- Check for related Aware module power or communication faults — a module with a power supply issue may log GPS device faults as a secondary effect.
- Contact Navistar service support if the antenna and cable check out, as the GPS component may require module replacement.
Can I Keep Driving?
Severity depends on active status, warning lamps, affected system, and related codes. Stop safely for red stop lamps, brake warnings, oil pressure warnings, high coolant temperature warnings, severe derate, or any abnormal vehicle-control concern.
Related Lookup Pages
Sources
- Navistar Aware Vehicle Intelligence Diagnostic Trouble Codes S08312 Navistar / International Truck Body Builder · oem · accessed 2026-05-05 · confidence high
Source: Navistar / International Truck Body Builder, Navistar Aware Vehicle Intelligence Diagnostic Trouble Codes S08312. This page paraphrases factual fields only and is not a substitute for the original document.
Open source - Navistar Engine Diagnostic Trouble Code Body Builder References Navistar / International Truck Body Builder · oem · accessed 2026-05-05 · confidence medium
Source: Navistar / International Truck Body Builder, Navistar Engine Diagnostic Trouble Code Body Builder References. This page paraphrases factual fields only and is not a substitute for the original document.
Open source
FAQ
Can a damaged GPS antenna cable cause Navistar Aware SPN 841 FMI 12?
Yes. If the GPS antenna cable is broken or shorted, the GPS module may lose the antenna connection and report an internal failure condition. Replacing a damaged cable sometimes clears what initially appears to be a device failure.
Is Navistar Aware SPN 841 FMI 12 repairable in the field?
If the cause is a damaged or disconnected antenna cable, field repair is typically possible. If the GPS component inside the Aware module has failed, the module typically requires replacement. Navistar service and the vehicle's telematics provider should be consulted for the specific repair path.
Will Navistar Aware SPN 841 FMI 12 affect any J1939 data other than position?
GPS-derived data includes position, heading, altitude, and GPS-based time synchronization. Engine data, speed from J1939 sources, odometer, and other ECM parameters are not affected by a GPS module failure.