22+ CUMMINS ECM SWAP ( ECM INSTALL )
Safety first
- Work in a well-ventilated, level area with parking brake on.
- Wear safety glasses and gloves.
- Disconnect both batteries before starting.
ECM removal and installation
1. Disconnect both batteries.
2. Remove the factory ECM.
3. Install the replacement ECM, making sure all mounting tabs and connectors are fully seated and secured. Failure to do so can cause internal ECM damage.
4. Re-assemble vehicle components as needed, leaving the inner fender liner removed if desired so you can inspect the ECM during initial power-up.
Electrical reconnection and checks
5. Reconnect both batteries.
6. Make sure the Cummins bypass cable (SGW) is plugged in correctly.
7. Turn the key to RUN (do not crank or start).
8. Clear engine codes (use your scan tool per its instructions). *HP TUNERS VCM SCANNER* OR ANY OBD 2 TOOL
9. Verify the red security/immobilizer light on the dash does not remain illuminated. If the light turns off:
- Crank and start the engine.
10. If the engine will not start or the red security light re-illuminates, stop and contact support.Final reassembly
11. Once the ECM and vehicle are confirmed to be working and the engine is idling properly, reinstall any remaining components (fender liner, trim, etc.).
Additional cable notes
- If using a CCV SOTF cable, ensure it is routed and connected correctly. Improper installation will cause drivability issues or improper SOTF function.
Transmission notes
- 68RFE transmissions require a quick learn procedure or about 500 miles of stop-and-go driving for the transmission to relearn and adapt.
- Our Cummins 68RFE tuning includes engine and transmission tuning. Expect firmer shifts and increased lockup due to higher calibration pressures — this is normal.
- Aisin TCM tuning is sold separately and also requires ~500 miles of stop-and-go driving to fully relearn shift strategies.
Final reminder
- Double-check all connectors, grounds, and cable routing to avoid future issues.
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