Hi,

 

Alphard, Ah20 2013, 18 speakers. 
 

I’m removing my amplifier, going to connect speakers directly to new head unit. 
 

I found this attached to the amp. Can anyone tell me what it does and whether I need to keep it plugged in?

 

Thank you. 

 

 

Looks like its the sonar computer, so it depends on whether you want the parking sensors to work i would say.

As Paul says, it appears to be the Clearance Sensor (as noted on the label).

 

The function is known as the Sonor on the air conditioner dash panel.

The function is switchable, and the distances adjustable (at least on the HDD unit).

Parking ECU, the sonar sensors, and cameras ( on the higher equipment spec) route through that. 

The reason it connects to amp is that utilise the drivers side dash speakers