PACCAR MID 128 PID 105 FMI 10: Meaning, Causes & Fix
Intake Manifold Temperature — abnormal rate of change detected
Diagnostic Reference
| Field | Details |
|---|---|
| Code | MID 128 PID 105 FMI 10 |
| Protocol | J1587 MID: 128 PID: 105 |
| Component | Intake Manifold Temperature Sensor |
| Manufacturer | PACCAR |
| Engine Series | MX-13 |
| Severity | 🟠 CHECK SOON |
| SAE Reference | SAE J1587/J1708 — MID 128, PID 105 |
Possible Causes
- Sensor response time degraded from soot/oil coating on probe tip
- Intermittent open circuit in sensor wiring from vibration
- Charge air cooler heat soak after prolonged idle
- Sensor reading wrong due to incorrect ECM calibration
- Aftermarket intake modification affecting sensor airflow
Diagnostic & Repair Procedure
- Step 1: Remove intake manifold temp sensor and clean probe tip with brake cleaner and soft brush
- Step 2: Graph temperature reading during warm-up with scan tool — should rise smoothly without jumps
- Step 3: Check wiring connector for loose terminals
- Step 4: Verify ECM calibration is latest available
- Step 5: Allow 2-minute cooldown after hot shutdown before recheck
Frequently Asked Questions
Is this a false alarm or a real problem?
CHECK SOON codes are rarely false alarms. The ECM has detected a parameter outside normal operating range. Sensor malfunctions can sometimes trigger false readings, but the majority of CHECK SOON codes indicate a developing issue that will worsen if left unaddressed. Use a diagnostic scan tool to verify sensor readings before replacing expensive parts.
Can I diagnose this without a scan tool?
Basic visual inspection can be performed without a scan tool — check wiring harnesses for chafing, connectors for corrosion, and related components for physical damage. However, to verify the fault, view live sensor data, and confirm the repair, a heavy-duty diagnostic scan tool (or a compatible OBD-II adapter with J1939/J1708 support) is strongly recommended for accurate diagnosis.
How soon should I schedule service?
Schedule service within the next 1–3 operating days. While the vehicle can continue operating normally, delaying repair increases the risk of the fault escalating to CHECK NEXT STOP severity. Additionally, some CHECK SOON conditions are precursors to emissions system faults that will trigger a mandatory derate if not addressed in a timely manner.
Related Fault Codes — MX-13
SPN 1077 FMI 14
🔴 STOP ENGINE
SPN 1347 FMI 7
🔴 STOP ENGINE
SPN 647 FMI 4
SPN 91 FMI 16
MID 130 PID 52 FMI 5
SPN 411 FMI 16
🟠 CHECK SOON
Associated Symptoms
References & Further Reading
- SAE J1939-73: Application Layer — Diagnostics. SAE International. Defines SPN N/A / FMI N/A fault code semantics for heavy-duty CAN networks. SAE J1939 Standard
- SAE J1587: Electronic Data Interchange Between Microcomputer Systems in Heavy-Duty Vehicle Applications. SAE International. Defines MID 128 parameter identification protocol. SAE J1587 Standard
- PACCAR MX-13 Service Manual: OEM diagnostic procedures for Intake Manifold Temperature Sensor faults. Consult the official PACCAR service documentation for your specific engine serial number.
- TMC RP 1210: Recommended Practice for Windows-Based Vehicle Diagnostic Interface. Technology & Maintenance Council (TMC) of American Trucking Associations.