The 3406E is the engine we see most. The 70-pin ADEM III module on 2WS engines is our fastest lane: 3 to 5 days on the bench, programmed back to your engine serial. 40-pin ADEM II units (5EK, 1LW, 6TS) and the older PEEC 3406B/C modules (4CK, 8TC) are repaired too, 15 to 30 days.
Failed flash recovery available.
On every Cat 70-pin ECM we repair, we upgrade the injector drivers for durability and replace the internal battery.
Sale through October 31: $525 on every Cat 70-pin repair (regularly $745). 40-pin and 120-pin repairs stay $745.
The 3406E has been on the road since 1994 and its ECMs fail in predictable ways. Almost all of it is repairable.
What you see: the battery went dead on the truck or machine, or it got jump started, and now it cranks and won't fire, or it won't do anything at all. It ran fine before the battery died. This is the classic ECM failure.
The quick check: turn the key on and watch the dash. The check engine light should come on for a few seconds. If it never lights up, there's a good chance your ECM is not waking up.
What we do: check the ECM fuses and battery cables first. If those are good, send the ECM in. We get it powering up again, test it on the bench, and send it back programmed to your engine.
What you see: A dead hole, a cylinder cutout test that shows one injector doing nothing, or a derate that stays after you swapped the injector.
What's happening: The injector driver stage inside the ECM has failed. On 3406E modules this is the single most common fault.
What we do: We rebuild the driver circuit and bench-fire every injector channel before it ships back.
What you see: The engine may run, but ET (or any J1939/ATA tool) will not connect. You cannot read codes or program it.
What's happening: The data-link side of the module has failed while the engine-control side still works, or the module is dead entirely.
What we do: We restore the data link on the bench so the ECM can be read and programmed again.
What you see: Key on, nothing. No ECM power, no injector pulse, sometimes intermittent after heat or vibration.
What's happening: Internal power supply or ground-path failure, often corrosion or a cracked joint on the connector side of the board.
What we do: We repair the supply and connector-side faults at the component level and load-test the module.
What you see: A string of 5-volt sensor codes at once (throttle, boost, oil pressure) that survives sensor swaps.
What's happening: The regulated 5-volt sensor supply inside the ECM is shorted or sagging.
What we do: We repair the sensor supply regulator and verify every sensor channel on the bench.
Don't see your exact symptom? Send it in anyway. We bench-test every unit before we tell you what's going on, and if we fix it the diagnostic cost you nothing.
Give us your engine serial prefix and we know which module you have.
| Arrangement | ECM generation / connector | Our bench |
|---|---|---|
| 2WS | ADEM III, 70-pin (157-3705) | 3-5 days |
| 1LW, 6TS, 5DS | ADEM II, 40-pin (117-4017, 145-7806) | 15 to 30 days |
| 5EK (1994-95) | ADEM II, 40-pin | 15 to 30 days |
| 4CK, 8TC (3406B/C) | PEEC, pre-ADEM (9X8085) | 15 to 30 days |
Self-ship free, or add a prepaid UPS label. Drop-offs in Princeton, MN by appointment. Include your engine serial number.
70-pin units: you pay the repair price at checkout, and if we can't fix it you get a full refund. 40-pin units: $350 bench fee, credited the same way. We tell you exactly what failed, usually within a day of receipt.
Injector driver repair, communication restoration, power-supply and 5-volt sensor supply repair, parameter recovery, whatever it needs. 3 to 5 days on the bench.
Programmed to your engine, every channel bench-tested, lifetime warranty on our work. Status email at receipt, at diagnosis, and at ship.
If yours is beyond repair, or the truck can't wait: remanufactured, bench-tested, programmed to your engine serial, 2-year warranty. Usually ships within 10 business days, often sooner.
On a 70-pin unit, you get a full refund when it is a normal failure we could not fix. We fix the large majority of the 70-pin ECMs that come in. The exceptions are when the ECM itself is the reason: a board that is cracked, burned, or eaten by water and corrosion, a proprietary chip that is no longer made, or damage from an earlier repair attempt. In those cases, and if your ECM tests good with nothing wrong, $150 covers the bench test, the written report and the return shipping, and we refund the rest. You can also put what you paid toward a tested exchange unit.
The 70-pin repair is $525 flat (sale through October 31, regularly $745), bench fee included, and 40-pin and 120-pin repairs are $745 flat. On 70-pin units you pay the repair price at checkout, before you ship it. If we can't fix a 70-pin, you get a full refund, unless the board itself is damaged beyond repair, a part is no longer made, or it tests good. Then $150 covers the bench test, the report and return shipping, and we refund the rest. 40-pin units start with a $350 bench fee that credits the same way. If it is not repairable we tell you first and offer a tested exchange unit with the bench fee credited.
We fix Cat 3406E ECMs every day. The 70-pin 2WS module is 3 to 5 days on the bench right now, plus 1-3 days return shipping. The 40-pin 1LW, 6TS and 5EK modules and the PEEC 4CK/8TC run 15 to 30 days.
Yes. Send your engine serial number with the unit and it ships back programmed and bench-tested, ready to plug in.
Usually. A dealer "no communication" or "failed" verdict is where most of our 3406E work starts. Send it in; the bench fee credits to the repair.
Related: Cat 70-pin ECM problems & symptoms · C15 ECM repair · C12 ECM repair · C10 ECM repair · C13 ECM repair · C16 ECM repair · C7 ECM repair · 3126 ECM repair
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"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."
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