PROGRAMMER MODE · 5

Your truck shuts off by itself at idle

Nine times out of ten it isn't a fault. It's a parameter called Idle Shutdown that turns the engine off after X minutes of idling. It gets switched off in the ECM, and it takes about two minutes.

Read this first

  • Several states have anti-idling laws. Turning this off doesn't exempt you from them — the ticket goes to the driver.
  • On a fleet truck this is usually set on purpose by the owner. Ask before you change it.
  • This procedure is for a DDEC IV on a Detroit Series 60. Other ECMs have different menus.

The steps

Diagnostic LinkIdle Shutdown (ISD)Enable Idle Shutdown

  1. Connect and open Diagnostic Link. Key on, engine off is enough.
  2. Go to the Idle Shutdown tab. It's abbreviated ISD.
  3. Look at the minutes. If it says 5, the engine shuts off after 5 minutes at idle. That's your answer. The field accepts 2 to 100.
  4. Uncheck Enable Idle Shutdown. It asks for a password: four zeros, 0000.
  5. Transmit. Send the change to the ECM and wait for it to confirm. Done.
Diagnostic Link with the ISD tab circled in red at the top right
The ISD tab, top right. That's where the parameter lives. Tap to enlarge.
The Idle Shutdown panel in Diagnostic Link, with the enable checkbox and the minutes field
The checkbox and, right beside it, the minutes. Tap to enlarge.
It still shuts off after doing this

Then it isn't Idle Shutdown. The usual suspects are a real fault putting the engine into protection, a battery or charging problem, or someone reprogramming the ECM and putting the parameter back. Send us the VIN and what it's doing.

Can I set it to more minutes instead of turning it off?

Yes, and it's often the better call: you keep the fuel-saving protection and stop the engine dying while you eat. Change the number instead of unchecking the box.

What about other ECMs?

The parameter exists on almost all of them, but the menu and the path change. We're covering them one by one in the series.

No laptop, no software, or you'd rather not touch it? We program ECMs by engine serial number with factory software, in Houston.

If they programmed it wrong

Guide for information only. Changing ECM parameters is the responsibility of whoever does it. Brand names indicate compatibility only; CTS is not affiliated with Detroit Diesel or Daimler Truck North America.