Detroit Diesel
DDEC flash code
Detroit Flash Code 77: Barometric Pressure Low
77 on Detroit Diesel engines means: Barometric Pressure Low. The failure mode (FMI 1) is “data valid but below normal operating range (most severe)”.
Code details
- Manufacturer
- Detroit Diesel
- Applies to
- Detroit Diesel Series 60 EGR (DDEC IV)
- Fault code
- 77
- FMI
- 1 — Data valid but below normal operating range (most severe)
- J1587 PID / SID
- PID 108
What to do next
- Read active and inactive codes with the OEM service tool (Detroit Diesel Diagnostic Link) and note the occurrence count.
- FMI 1 tells the shop the type of failure to test for: data valid but below normal operating range (most severe).
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
- Detroit Flash Code 77 — Barometric Pressure High
- Detroit Flash Code 77 — Engine Oil Pressure High
- Detroit Flash Code 77 — Turbo Boost Pressure Low
- Detroit Flash Code 77 — Fuel Temperature High
- Detroit Flash Code 77 — Relative Humidity Above Range
- Detroit Flash Code 77 — Relative Humidity Below Range
- Detroit Flash Code 86 — Barometric Pressure Sensor Input Voltage High
- Detroit Flash Code 87 — Barometric Pressure Sensor Input Voltage Low
Source: Detroit Diesel Series 60 EGR Technician's Guide, DDEC IV EGR fault code table (Table 4-1). See also OBD-II codes.