I have an 02 KR and the audio system used to adjust the volume automatically depending on the speed of the vehicle. This recently stopped working and now there is no adjustment based on speed, just one volume level at all speeds. I talked to one Ford dealer who informed me that it was the head unit which controls this and it would need to be replaced. I don't think this is correct though, as the radio would not be able to detect the speed of the vehicle by itself and would therefore have to rely on a "sensor" of some type to feed it the vehicle speed data. I believe this is probably what is not working but I do not know where this sensor is located or what it is called (part # or otherwise), so I am asking for your help. Does anyone have any info on this?

 

Have you recently unhooked the battery? There is a control for the speed sensitive volume on the head unit. You have to have the radio on and push and hold the power button until the menu says "speed" or something to that effect. If you have unhooked the battery or the radio for that matter, I think this may reset itself to the factory default which is 0. The numbers go from 0 to 7 I believe and 0 is no change to the volume, 7 is the most extreme change. Just wanted to make sure you knew how to work it to make sure it defintiely is not working.

 

In all honestly, I don’t think there is an actual sensor that hooks up to the speedo. I believe the SSV function works similar to those found in Radar detectors, which essentially monitors the engine noise. When idle, the volume is lower, however during acceleration, the engine noise increases, and thus so does the radio via the SSV. That would explain why the proposed solution would be replacing the HU. Although, “IL6fan” may also be onto something, since you lost power, the SSV setting may have bee set back to the factory default (off).

 

To my recollection, there is a speed pulse wire in the wiring harness that controls this function. My assumption is that it's getting a signal from the PCM on movement.

Doesn't the head unit have a adjustment (similar to bass, treble etc) that allows to adjust the speed volume feature? Have you checked this?

-RP-

 

There is not a separate control button for the speed sensitive volume. I checked mine this morning. With the radio on, push and hold the volume button. It wil come up "SPEED VOL X" with X being a number. The lower the number the less the change in volume will be, the higher the more the change in volume will be. I was just trying to make sure he knew how to adjust it before replacing anything. Make sure it still works.

 

Looks like some of them are different. Some of them are in the audio options and some you have to push and hold some different buttons to access.

 

Could be. Mine is an '03. Might be different in the '01-'02's?

 

You are 100% correct sir. I tried what you reccommended today and now it works great again. I had unhooked my battery to install a battery blanket (cold Canadian winters eh) and that is when it quit working. Oddly enough though, the service guy at the Ford dealership was not aware of this adjustment in the head units. I appreciate the help and hope that you are around the next time the guys at Ford draw a blank. Thanks again.

 

Not a problem and glad I could be of help to you. It's always nice to get something fixed easily like this rather than taking it apart only to realize you didn't really have to. And I have spent some time in Canada in the winter. Used to travel a lot in my previous job. It definitely gets cold up there in the winter months. Battery blanket is a good idea I'm sure.

Cheers eh!

 

Thanks folks, you helped me fix a problem I didn't even know I had.

 

Cool, glad it helped you too.