Squeak from Prius within the first few hundred feet

Nope.

But I do get the noise that the car makes when in EV mode, so that pedestrians are aware of the car. And a noise when the ICE kicks in

 

And a noise from the brake pads touching the rotors as I slow my descent from the garage to the street.

 

Brakes are designed to "squeak" when the pads are about worn out.
Have that checked.

 

It'll be the petrol engine firing up the first time. As you start up, press the EV Button:

and the EV Mode light will turn OK.

Then watch the EV Mode light turn OFF as you hear that sound:
.

 

If your car is like mine, this happens when the speed reaches 12 mph for the first time in each drive cycle, and it’s probably the brake test discussed in a previous thread. In the Repair Manual, Toyota writes:

“When the vehicle speed reaches approximately 20 km/h (12 mph), the initial check of the brake actuator assembly is performed and pump motor operation sounds are generated.”​

They explain further, in the topic for diagnostic trouble code (DTC) C1427:

“When the power switch is on (READY), the stop light switch assembly off and the vehicle speed is 20 km/h (12 mph) or more, the skid control ECU (brake booster with master cylinder assembly) performs a self-diagnosis of the ABS motor relay circuit during the initial check of the actuator.”​

and in the topic for DTCs C146C and C146D:

“If a speed signal of 20 km/h (12 mph) or more is sent to the skid control ECU (brake booster with master cylinder assembly) with the power switch on (IG) and the stop light switch assembly off, the ECU performs self diagnosis of the motor and solenoid circuits.”​

 

Anybody get a plastic rattle from the radar cruise covering at the center of the windshield? It doesn't happen always but it annoys me when it rattles. I always think it's my sunglasses in the compartment but when I remove my glasses it still rattles. The dealer that I service my Prius at said they took apart the housing and fixed the problem.

 

The RADAR unit is in the centre of the grille:

 

I mean the radar cruise camera mounted in front of the rear view mirror. There is a plastic housing around it and mine rattles more often than I like. I thought only Kitt from Knight Rider had a sensor on the front center of the car.

 

There's a forward recognition camera (and other sensors too) on the windscreen which works in with the RADAR sensor.

 

The brake wear indicator often DOES make it's noise while the brakes are NOT applied.

 

I was gonna say the same thing, as it doesn't sound right but I learned thru the forum its a Prius noise. Good write up! I was gonna say at 14MPH mine does this but I guess its 12.

 

Check for rodents!!!

 

I also hear this squeak before launching the gasoline engine. The sound of magnetostriction. Speed 70 km / h. Addressed to the dealer, and could not understand.