$1,295
+ $500 refundable core deposit (90-day return window). No-deposit option available at checkout: send your core first.
Usually ships same day on orders in by 2 PM CT
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2-year transferable warranty · Programmed to your truck at no charge · Core deposit refunded on return
Prefer to fix your own unit?
Flat rebuild $545 (bench fee included) · 3-day turnaround — you keep your original ECM.
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Part Number4090071
BrandCummins
ConditionRemanufactured
SKUNL-CUM-4090071

About the Cummins Ram 5.9L (CM848B) ECM

The 4090071 is the engine control module for the Cummins Ram 5.9L (CM848B).

We repair this ECM on the bench and stock tested, remanufactured exchange units, programmed to your engine and ready to install. Send yours in for repair, or buy an exchange unit off the shelf.

Remanufactured Cummins ECM for Dodge Ram 2500/3500 5.9L Cummins pickup, P/N 4090071 (module family CM848B). Programmed to your VIN and engine data. Plug and play install. Standard programming included — usually ships same day on orders in by 2 PM CT. 2-year warranty. Core exchange required. $500 core deposit refunded when your old ECM returns within 90 days.

Common Cummins ECM failures we repair

We fix these on the bench every day. Wiring and connectors can mimic ECM failure, so we test first.

  • Injector driver faults. The circuits that fire the injectors burn out or go weak, so the engine misfires, runs rough, or loses a cylinder. We rebuild these driver stages on the bench.
  • No communication. The module stops talking to your scan tool over J1939, usually from a failed internal power supply. We track the dead spot and bring it back.
  • Heat, vibration, and intrusion damage. Cracked solder joints, blown fuses, and oil or moisture in the board cause faults that come and go. We repair them at the component level and bench-test before it ships.
More on Cummins ECM repair →

Verified Google reviews

What truck owners & shops say

★★★★★
"Mike does great work and sent my repaired ECM back to me right away. Saved me thousands of dollars vs. using the dealer. Would recommend to anyone that needs prompt repair."
Michael B. via Google
★★★★★
"From ECMs and harnesses to straight-out cutting counter bores in-frame for us. Great shop — and a great person to have in your pocket."
Mega24v via Google
★★★★★
"Highly recommend these guys! Fast turnaround — I had my ECM back and repaired by the next day. Will definitely do more business in the near future."
Javon Z. via Google
★★★★★
"Michael is a diesel guru. He made my rig scream and had it done when he said, for the price we agreed to. I'd highly recommend him."
Glenn S. via Google
★★★★★
"Mike is highly knowledgeable in all areas of diesel repair — from mechanical work to advanced electrical diagnostics. You can count on him to get the job done right."
David F. via Google
★★★★★
"Mike is a very professional and skilled mechanic. I highly recommend him for any of your needs."
Justin N. via Google

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