Detroit fault code 3216 FMI 2 GHG14 is the TruckFaultCodes.com diagnostic sheet for the SCR NOx Inlet Sensor Rationality Error condition on Detroit DD-series engines. This 3 pages reference lists the fault identification, monitored conditions where shown, and the step-by-step troubleshooting the technician follows in the shop.
Official document details
| Brand | Detroit |
|---|---|
| Model coverage | Detroit DD Series (EPA 2007-Current) |
| System / Group | DD Series (EPA 2007-Current) / DTCs |
| Publication no. | Not printed; TruckFaultCodes.com reference |
| Year / Revision | 2017 |
| Pages | 3 |
| File size | 0.3 MB |
| Format | |
| Language | English |
Document table of contents
- Fault code identification (SPN 3216 / FMI 2)
- Description and enabling conditions
- Air inlet, CAC and EGR inspection
- Parameter charting with the diagnostic tool
- High-idle regeneration and log submission
3216 FMI 2 GHG14 troubleshooting steps
The sheet monitors SCR In NOx. Enabling conditions are fuel mass at zero, DPF outlet temperature above 200 C, battery voltage above 10 V and engine speed between 500 and 2100 rpm for more than 30 seconds. Typical duration is 5 seconds, the dash lamps are none, and the engine reaction is none.
The three-page routine first repairs any other active faults, then inspects the air inlet, Charge Air Cooler (CAC) and EGR piping for leaks. An Idle Speed Balance (ISB) test checks for a faulty injector and the Aftertreatment System (ATS) is examined. With the diesel diagnostic tool connected, engine speed, SCR inlet and outlet temperatures, both NOx sensors and NOx conversion efficiency are charted. The Diesel Exhaust Fluid (DEF) dosing unit is disconnected, a high-idle regeneration is run, and the log file is submitted to the Detroit Customer Support Center at 800-445-1980.
Applicable truck models
This sheet applies to Detroit DD-series diesel engines (the DD13, DD15 and DD16 family) built under the EPA 2007-Current emissions platform, in its GHG14 calibration. Engine and emissions specifications should always be confirmed against the vehicle build; full engine information is published on the Detroit Diesel official site.
Who needs this 3216 FMI 2 GHG14 manual
Technicians investigating an SCR inlet NOx sensor rationality complaint use this sheet to chart the NOx system and confirm conversion efficiency before parts are ordered. It is a quick bench reference rather than a full workshop manual, so the named removal steps still route back to Power Service Literature and, where escalation is needed, to the Detroit Customer Support Center.
The full PDF is available in the DiagTechPro manuals library; a free account is required to download it.
Related manuals library
