Tone and relay clicking noise

ranger pete · #1 07-11-2011, 04:32 PM

About a month or two ago, shortly after leaving for work in the morning, I started to hear a low pitched tone which is accompanied by a relay click at the start and finish of the tone. It's not particularly loud. I you have the radio turned up, you might miss it. The tone/clicking is intermittent. Anywhere from momentary to maybe a second or two in duration. The best way to describe it is that it sounds like something you hear in the headphones during a hearing test. And it is closer to the low end of the spectrum than the high end.

It did it pretty much all the way to work, about 20 minutes, then went away until yesterday when I heard it near the end of a 2 hr drive to mass. it came back on the way home, on and off for an hour or so. It did not happen on the drive to or from work today.

It appears to be coming from behind the glove compartment, I think. Definitely somewhere on the right side of the dash or maybe right kick panel. Kinda hard to narrow it down while driving and it hasn't happened with a passenger in the truck yet.

It is a pretty much stock 97 v-6 ext cab 5 speed. roll up windows, ac. no cruise.

i also have an issue with the air temp control. it stays hot unless i have the AC on, in which case it gets reasonably cool.

djfllmn · #2 07-11-2011, 04:52 PM

sounds like something is up with the blend door

ranger pete · #3 07-11-2011, 06:10 PM

makes sense. is that what that tone is?

djfllmn · #4 07-12-2011, 04:13 AM

could be the acutator trying to move

FireRanger · #5 07-12-2011, 04:27 AM

I have no idea what the tone and relay clicking is. There is nothing that would do that in the truck normally.

The blend door is why you have AC issues. There is no relay and nothing to click. Totally separate issue. There is an electric actuator accessible under the dash that rotates the door to open or close flow to the heater core. If the actuator is unplugged broken, it will not move the door. If the door linkage is broken, it will also not move. Result is the door is stuck in full heat. Putting the controls on MAX AC closes a hot water valve to the heater core preventing any heat from being applied.