B2200, B2600i 2WD, Miata & MPV 2.6L

WARNING: This page is about a different car, the 1992 Mazda Navajo. However, it is still accessible from the selected car via links, so may be relevant.

Kickdown and 4-3 switch is located on upper part of accelerator pedal. To adjust kickdown section of switch, use steps 2) and 3). To adjust 4-3 section of switch, use steps 4) and 5).
Connect voltmeter between terminal "C" and ground. See Fig 1 . Turn ignition on. Depress accelerator pedal fully. Voltmeter should read less than 1.5 volts until pedal is at least 7/8 depressed. Battery voltage should be present at or after 7/8 pedal travel.

Fig 1: Testing Kickdown & 4-3 Switch (B2200, B2600i 2WD, Miata & MPV 2.6L)
Courtesy of MAZDA MOTORS CORP.
If voltage is not correct, disconnect switch and check continuity between terminals "C" and "D" when tip of switch is depressed .24-.26" (6.0-6.5 mm). If continuity is not present, replace switch. If continuity is present, adjust switch until battery voltage is present at 7/8 of pedal travel.
Connect voltmeter between terminal "A" and ground. See Fig 1 . Turn ignition on. Depress accelerator pedal to limit. Voltmeter should read less than 1.5 volts until pedal is at least 3/4 depressed. Battery voltage should be present at or after 3/4 of pedal travel.
If voltage is not correct, disconnect switch and check continuity between terminals "A" and "B" when tip of switch is depressed .14-.18" (3.5-4.5 mm). If continuity is not present, replace switch. If continuity is present, adjust switch until battery voltage is present at 3/4 of pedal travel.