Overspeed warning horn.
 

I have a 2000 Z28 convertible that does not get driven much due to the overspeed warning horn. It is so annoying that since new it has only done 30,247 kms... Our speed limit here is 110 or 120 kms on most highways. Higher on some others. The overspeed warning horn comes on at about 116 kms and won''t go off until slowing down to 106 kms.. I have looked every place I can think of near where the annoying screeching comes from. Then, when not finding how to stop it, I put the car back in storage until the next time I feel the need to play with the car. Any words of wisdom on my delima? This car has been just one issue after another---good thing I am a loyal GM fan or it would have been taught to swim a long time back. Help please.:icon_frown:

I looked through the 2000 service and owners manuals and can find no mention of an overspeed warning. Obviously, your car seems to be an export vehicle and that could make a difference. Have you checked your owners manual? I would think if the car was equipped with an option like that, the export owners manual would give some explanation of its operation.

Thanks for the reply. Have almost memorized the manual. Only informs about the over speed sounding and then when it will go off. No further information. Will just put it back in storage.

Must be an export thing for sure, my 2001 has nothing like that.
Maybe a tuner with a good computer can turn it off or change the speed it comes on to a higher point.
My guess is it's tied into the car's PCM and it will take a computer to do anything with it.

I'm agree with Y2Keglide, this would most likely be controlled by the PCM and you may have to get access to Tech 2 scanner. There is a vehicle speed sensor on the transmission, generating a voltage that is sent to the PCM. The PCM uses this signal to display the speedometer reading along with controlling other vehicle functions. It may be possible the limit could be raised using a scanner, but I couldn't find anything mentioned about the subject. Out of curiosity, what would be the conversion of 116 kmh to mph be?

Here's a link to a pdf copy of the 2000 factory service manual if you don't have one. Maybe it can help with your search for information to find your problem. http://www.mediafire.com/file/21djvr...arked.pdf/file

Fine horn, unplug it LOL, If one of my camaro had one it would have been going off every day. I use my Phone for a GPS and one time after an update it turned on the speeding warning. I made it 3 miles from my house before I pulled over and found the setting to shut it off. :)

km/hmph

116.2872.253 72.253mph

Have a Tech I for my corvettes and cannot find anything to disable it. Can do everything else I expected to find using the Tech I but nothing on the bloody noise maker. Seems to be coming from just to the left of the glove box but it must be invisible.

You might want to stop in at https://ls1tech.com/forums/

Thanks. Always appreciate suggestions.

Correct me if I'm wrong, but doesn't the Tech 1 scanner use different system program cartridges' to allow a person to troubleshoot a particular problem? If so, I'm not sure it has the capabilities of the later Tech 2 to access all the functions of the 2000 model year vehicles. For example, the Tech 1 supported a different set of Digital Troubles Codes than the latter Tech 2. I know the Tech 2 has the ability to be use with earlier model cars, but I don't know if the Tech 1 can be used with a later model car. Anyone know the answer to this?