Checkout Current Transformers (CTs) and check resistance across each one while it is disconnected. All resistances should be within 10% of one another. Also do a diode test on the CT inputs on each compressor module. (The diode test is described in RTAA-SVB10B-EN.)
[pdf] Disassemble the air compressor cylinder head. Refer to Procedure 012-106. Use a coupling puller, Part Number 3376663, or equivalent, to remove the spline coupling hub. Remove the front thrust bearing. Remove the three flange head capscrews. Remove the three captive washer capscrews.
[pdf] Use your Phillips head screwdriver to loosen the screw located either on the top or on the side of the cover. Unhook all of the black and white wires from the pressure switch using the needle nose pliers. Take a 5/16” nut driver and remove the ground screws, holding down the ground wires.
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