About 2 weeks ago on a trip to Sand Diego from Phx a strange and yet rythmic sound started eminating from the dash. It was a "click buzz click" sound. Nothing I did made it stop (AC on-off, Light Switch on-off, etc). It did cease once in SD and didn't really occure again until a couple days ago.

Now this morning I head off to Home Deperate and my headlights will not shut off unless I do the dome override trick which didables the DR too ( I like the DRL with amber lights and all).

Can anyone tell me what this could be? I have a feeling a relay was going, hence the "click buzz click" sound and the healights staying on are the result.

I don't have the service manual for the truck yet, but perhaps someone has had this happen to them or could proved the digram, location or the circuit.

Thanks

I think you have two problems....

1) You've knocked the daylight sensor down into the dash. It's a black bubble just right of center in the middle of the dash flat portion. http://www.dieselplace.com/forum/showthread.php?t=284894&highlight=sensor

2) You've got a failing temp or duct actuator in the HVAC, hence the noise. While the following is for an '03 or newer, there is a similar actuator family in yours, with the difference being the control panel itself. Connection to a Tech II at the stealer, in the AC actuator test mode, will reveal which one is bad.
http://www.dieselplace.com/forum/showthread.php?t=254111&highlight=actuator

Thanks heymccall, but I got a follow up to this.

The little dome is still present on my dash, so unless the dome is a cover and the sensor is underneath I don't "Think" that a fall through is the problem but it may give a direction to start looking.

On the subject of the A/C making the noise; would the definition of Intermittend be: on/off noise continuously any time the vehicle is in operation? My symptoms seem to be sporadic from day to day, even missing days. In fact I haven't heard it for 2 days now.

Just want to be relatively sure before I shell money to a stealer...

Thanks again.

The sensor is integral to the bubble, but being a photovoltaic eye, I suspect it may have actually gone bad, versus the normal "fell through" syndrome. Perhaps shining a bright lamp upon it will allow you to see if it's lost it's sensitivity. Place a bright lamp above it before starting the truck.

As for the AC actuator, it will dependent upon outlet selection, or right side temp selected, or left side temp selected. The noise will most likely be present when you've made a change in temp or airflow, and, at that point, you should be able to narrow down the noise to the specific area. The Bonneville I just ran through here made noise when requesting full heat driver's side, otherwise it was quiet. As for the dealer, I'd be a little more sure it's an actuator, as many dealer techs will empty your wallet on this type of problem due to lack of experience with the system, and a lack of knowledge of the available test modes within the scanner. There is a sweep and position test within the scanner they possess.

I was wondering if the EFI-Live can re program the A/C modules?

Anyone?

I was wondering if the EFI-Live can re program the A/C modules?

Anyone?
Nope. AFAIK, EFI-Live cannot address the BCM or the HVAC module.