Optimized Idle.

I was told that beep was a safety feature to let people know the engine was about to crank so they can remove their hands if they were working on the motor, so if they were telling me the truth then I doubt they've "fixed" it.

Why anybody would be working on the motor with the Optimized Idle turned on is a mystery to me.

That beeping never woke me up, but the shaking of the truck when the engine fired up and shut down sure did.

 

My truck has a subtle beeeeep that can barely be heard. But on most trucks, if you open the hood, it has a hood-tilt sensor that shuts down the opti-idle, unless a shop jumps it to check something out that needs to have the engine running and uses opti-idle to override the company idle limiter...

 

You may wish to find the source of the beeping and remove it should you encounter one.

I had a pickup truck that made a truly obnoxious buzzing noise whenever the door was open. One day, I sought it out and found that it was a chip (like a fuse) that could be pulled out.

Once I pulled it out, the buzzing alert stopped. I took a hammer to it anyway.
Few things on this earth can match the satisfaction gained from an annoyance being destroyed with blunt force trauma.

 

It may need it to complete the circuit. My company has that stupid nanny-crash crap in the front. One of the previous trucks crash beep was so loud it gave me a headache. So I unplugged the tweeters in the door...then it threw a warning on the dash display about the speaker connection. My son-in-law's mom's new truck had a seatbelt warning...so he clipped the seat sensor wire so it didn't know anyone was sitting there...then the truck wouldn't start because it didn't detect the sensor, so he had to repair the wires. The same may be true with the new trucks out here with opti-idle, without the warning beep drawing amps before it starts might cause an issue...a ball of duct tape around it muffles the sound if it's loud.

 

I've never had a truck with Opti-Idle. It's a good question to have answered by drivers at any company before you hire on. Recruiters, dispatchers, etc don't answer this question. Don't ask them.

 

Count that fact among your blessings.

 

Most have the beep same as yours. It’s less annoying than the one from 20 years ago.

 

Freightliner still has a beep but it more quiet now I would say. Freightliner now has electric APU to run electric a/c for sleeper when parked and diesel fired coolant heater to heat sleeper.

The big improvement is the system has 8 batteries now on the truck, but it still not as good as regular apu in my opinion. It quiet no and stuff but in extreme cold 5 to -5 it need more heater. Above 90 it needs more a/c. The 8 batteries will run the system 8-10 hours without optimized idle starting the engine to recharge batteries. It does have Interior Comfort Mode, something is wrong with my 2020 truck because it won't start in colder temps and no fault codes show up.