The Detroit DDEC ECM failures we see most

These show up across these ECMs week in and week out. If your symptom is on this list, that is good news. It means we have seen it before and it is fixable.

Internal memory battery (flat $450)

What you see: lost parameters after the truck sits, a battery code, or a DDEC IV or V that drops its settings.

What's happening: the soldered-in memory battery inside the module has gone flat, so the ECM loses what it is supposed to remember.

What we do: we replace the internal battery for a flat $450, preserve your parameters, and bench-test the unit before it ships back.

Injector driver failure

What you see: a dead hole, misfire, or rough run that follows the ECM and not the injector.

What's happening: the driver circuit inside the module that fires the injector has failed, so the ECM stops driving one or more injectors.

What we do: we rebuild the driver circuitry and bench-test every injector channel before it ships back.

No communication, dead module

What you see: the ECM will not talk to DDDL or your diagnostic tool, or the module is completely dead.

What's happening: the internal power supply or communication section has failed, often from age, a voltage spike, or moisture intrusion.

What we do: we trace and restore the power and communication side on the bench so it can be read and programmed again.

Don't see your exact symptom? Send it in anyway. These are the common ones, but these ECMs fail in other ways too, and we test every unit before we tell you what is going on.

How a Detroit DDEC ECM repair goes

  1. 1

    Ship it in

    Self-ship free, or add a prepaid UPS label. Drop-offs in Princeton, MN by appointment.

  2. 2

    We test it

    $350 bench fee, credited toward the repair. We test it and tell you exactly what failed, usually in 1-2 business days.

  3. 3

    We fix it

    Internal battery replacement, injector driver repair, power and communication restoration, whatever it needs. Standard turnaround 3-5 days on the bench.

  4. 4

    Back to you

    Programmed to your engine, bench-tested, and backed by our repair warranty. Plus 1-3 days return shipping.

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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