The Volvo and Mack 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.

Injector driver failure

What you see: a dead bank or a single injector electrical fault, a misfire, or a rough run that follows the ECM.

What's happening: a failed injector-driver output circuit inside the module, often after a harness short took the driver with it.

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

No communication, J1939 loss

What you see: the ECM drops off the J1939 bus, will not talk to your tool, or the truck goes to a no-start.

What's happening: the internal communication or power section of the module has failed. We separate that from harness corrosion so you fix the right thing.

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

Oil and water intrusion

What you see: intermittent faults that come and go, corrosion on the connector, or a unit that acts up after a wet or oily season.

What's happening: the injector harness pass-through can leak oil into these units and moisture corrodes the board, a known weak point on this family.

What we do: we clean and repair the corrosion, rebuild the affected areas, reseal the unit, and bench-test it before it ships.

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 Volvo and Mack 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

    Injector driver repair, communication restoration, corrosion and intrusion repair, 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

Read more reviews & leave your own →

Email us about a problem unit.

It comes straight to our inbox. A diesel tech reads it and answers, usually the same business day. Tell us the engine and what it's doing, and we'll let you know whether we can help.

Email us [email protected]

Send a quick question

Two fields. Goes to our inbox; we reply by email.