The way Zak did it on his '94 won't work on your '99.

I recently installed a pushbutton switch that silences the warning chime on my '99 when the driver's door is open (the passenger door does not engage the warning chime on my '98).



(The seat is all the way back so you can see the button pretty good in the pic, but when the seat is in the normal positon it's hidden quite well).

The "door chime mod" has the following features:

- Pressing the pushbutton silences the annoying chime when the key is in ACC mode and the driver door open. It also shuts off the interior lights (unless they are on for a reason other than a door being open).

- With the engine running and the driver door open, hitting the button shuts off the interior lights and also turns off the "door ajar" light on the instrument panel:

- If the pushbutton is not operated, the chime works exactly as it did from the factory;

- Chime operation reverts back to factory whenever the ignition switch is moved from ACC or the driver door is closed. This "automatic re-enable" reduces the risk of locking the keys in the truck;

- Headlight warning chime is not affected by this mod.

As far as I know, it works the same on a '99 as it does on my '98.

I can't post the link to the mod here, it's from another Ranger forum (which means it'll get nixed). PM or email me if you're interested, and I'll get it over to you.