With no power applied, measure resistance between the two large terminals. You should see infinite resistance (OL) β the switch is open.
Set your DMM to Ohms (Ξ©). Measure resistance between the two small terminals (the coil). A healthy AACT 425 should read between 10 and 30 ohms. An open circuit (OL) indicates a burnt coil. A short (0 ohms) means the coil is fried. aact 425
Next time you see a liftgate smoothly raise a pallet of bricks or a winch pull a vehicle from a ditch, remember the vital click of the AACT 425βthe relay that works tirelessly behind the scenes, duty cycle after duty cycle. With no power applied, measure resistance between the
Apply 12V directly to the two small terminals (polarity doesn't matter for a SPST solenoid). You should hear a loud click . Now measure across the large terminals again. Resistance should be less than 0.5 ohms. Higher resistance indicates pitted contacts that will cause voltage drop and heat. Measure resistance between the two small terminals (the