Sounds like a relay clicking in the dashboard

[David Hamrick]

Driving a 2015 Silverado 1500.  Starting to randomly hear what sounds like a relay switching on and off, sometimes slow, sometimes rapid fire.  The sound appears to be right in front of me, and I would say high in the dashboard as opposed to lower.  It only happens at 65MPH or higher, and when driving straight or when the wheel is moved left (counterclockwise).  I have not noticed any effect on the vehicle driving operation.  What other questions come to mind?

 

**Edited to add** The clicking is present regardless of power to HVAC system.  

 

Actually went back out and checked that the HVAC system is working all temps, all locations with no noises.

Edited May 24, 2025 by David Hamrick

[richard wysong]

Probably a blend door motor on the a/c heater either out of sync or stripped gear.

[David Hamrick]

...

 

Edited May 23, 2025 by David Hamrick

[David Hamrick]

1 hour ago, richard wysong said:

Probably a blend door motor on the a/c heater either out of sync or stripped gear.

Would this happen in the HVAC system is turned completely off?

 

[richard wysong]

As always the first step is to check for codes, the parts store "free" scan may not do body codes so you may have to pay your local garage to do a scan. Their scanners are expensive with yearly software updates around $1000 so don't expect it for free. Try playing with the temp and mode controls while it's making the noise and see if it changes or stops