This Detroit ambient pressure CAN reference documents fault code SPN 108/FMI 13 (Ambient Air Pressure Signal Not Available Via CAN) for Detroit DD-series engines with ACM, MCM and CPC on PT CAN. It reproduces the original TruckFaultCodes.com fault tree, from the first check through the final repair, so the code can be confirmed and worked in the exact order the factory intended. Each step lists the measured value or check and the pass or fail branch that follows, matching the layout used in the source document.
Detroit ambient pressure CAN troubleshooting overview
This sheet covers an ambient air pressure value missing from the CAN bus. After a reprogramming check it has the technician power the modules down for five minutes, reconnect the diagnostic tool and re-read codes. If faults remain active it points to the SPN 625/FMI 9 PT CAN procedure. Follow the checks in sequence and verify the repair before clearing the code and releasing the vehicle.
Official document details
| Brand | Detroit |
| Model coverage | Detroit DD-series engines with ACM, MCM and CPC on PT CAN |
| System / group | DTCs — ambient air pressure CAN signal |
| Fault code | SPN 108/FMI 13 |
| Source publication | TruckFaultCodes.com (© 2017) |
| Pages | 1 |
| File size | 0.2 MB |
| Format | |
| Language | English |
Document table of contents
- Fault code identification — SPN 108/FMI 13
- Reprogramming check (ACM, MCM, CPC)
- Module power-down for five minutes
- Diagnostic-tool reconnect and code re-read
- Redirect to SPN 625/FMI 9 PT CAN troubleshooting
Applicable truck models
It applies to Detroit DD-series engines with ACM, MCM and CPC modules communicating over PT CAN. Always cross-check the reading against any companion codes before condemning a component. For the official product and service literature, visit the Detroit Diesel website.
Who needs this Detroit ambient pressure CAN manual
Technicians who need to know when a missing ambient-pressure signal is a CAN network problem rather than a sensor. It is written for shop use as a quick, printable reference to keep beside a diesel diagnostic tool during the job.
The full PDF is available in the DiagTechPro manuals library; a free account is required to download.
Related manuals library
