If it has the Etac style display and is similar to the Toyota 7FBW23 jack, You hold the horn button down prior to turning on the key, then as the display lights up you will see letters, when you come to "P" (program), you release the horn button and use the forward and reverse control to scroll thru your settings. Setting 1 should be 42, and settings 3 and 5 should be 90 or 100. To change the settings you again push the horn button when you scroll thru and when your hour meter icon flashes, you change the value using the forward and reverse control. to save hit your horn button again and key off.