International (Navistar)
Navistar DTC
International Fault Code 621: Engine using mfg. default rating
621 on International / Navistar trucks means: Engine using mfg. default rating.
Code details
- Manufacturer
- International (Navistar)
- Applies to
- International / Navistar engine (DTC index)
- Fault code
- 621
- Component / signal
- ECM
- Truck models in source
- 3200, 4100, 4300, 4400, 7300, 7400, 7500, 7600, 7700, 8500, 8600, BE 200, CE Bus, CXT, DuraStar, LoneStar, MXT, ProStar, RXT, TranStar, WorkStar
What to do next
- Read active and inactive codes with the OEM service tool (Diamond Logic Builder can clear previously active codes) and note the occurrence count.
- 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
- International Fault Code 621 — Engine Using Mfg. Default Rating Program Engine
- International Fault Code 111 — No errors detected - flash code only
- International Fault Code 613 — ECM/IDM software not compatible
- International Fault Code 614 — EFRC/ECM configuration mismatch
- International Fault Code 623 — Invalid Engine Family Rating Code (EFRC)
- International Fault Code 631 — Read Only Memory (ROM) self test fault
- International Fault Code 632 — Random Access Memory (RAM) - CPU self test fault
Source: Navistar diagnostic trouble code index (HNC Truck Parts). See also OBD-II codes.