TECHNICAL GUIDE · OBD VS BENCH
OBD vs Bench Mode — When to Pick Which Read Method
Practical decision guide: when OBD-mode read is enough, when bench-mode is required, and how to choose between them for different ECU variants.
Table of contents
Quick decision matrix
| ECU family | OBD? | Bench? | Recommended |
|---|---|---|---|
| EDC15 | YES | Not needed | OBD |
| EDC16 | YES | Not needed | OBD |
| ME7 | YES | Not needed | OBD |
| EDC17 | YES (TPROT v1-v5) | Backup | OBD |
| MED17 | YES | Backup | OBD |
| SIMOS | YES | Backup | OBD |
| Delphi DCM | YES | Backup | OBD |
| MG1CS / MD1CS | Partial | YES | Often bench |
| MD1CS006 (OM654) | NO | YES | BENCH MANDATORY |
| MG1CS024 (M139) | Partial | YES | BENCH MANDATORY |
When OBD is fine
- ECU on the supported list for the variant.
- Customer wants Stage 1 or DPF/EGR/AdBlue off — no boot-locked security.
- Vehicle has healthy battery, no electrical gremlins.
- Time-sensitive — OBD-mode read is 30-60 min faster than bench.
When bench is required
- ECU variant on the not-OBD-flashable list (newer MD1/MG1 boot-locked variants).
- OBD security access failed — calibration key not yet bypassed.
- Recovery from a bricked ECU — boot-mode bypasses corrupted bootloader.
- ECU from a parts vehicle with no battery / harness to power OBD.
Platform-by-platform
See per-family ECU pillar pages for the OBD vs bench recommendation specific to each variant.
FAQ
Is OBD ever faster than bench?
Almost always — bench mode requires ECU removal which adds 30-60 min. OBD wins on speed when both work.
Can I switch mid-job?
Yes if your flasher supports both. Try OBD first; fall back to bench if security access fails.
Are bench files different from OBD files?
No — same binary content. The transport differs but the file is identical.