COMPRESSOR-A/C 3971026 - Caterpillar

24 Volt Products Equipped With Batteries and Disconnect SwitchesWhen replacing the batteries, battery cables, or disconnect switch, use the following procedure to reduce the possibility of sparks at the battery or cable connections.
1. Turn off the start switch and all electrical loads such as wipers, heater motors, etc.2. Turn off (open) the disconnect switch and remove the key.3. If the machine is equipped with an electrical supplemental steering attachment (example: Off Highway Trucks, Motor Graders), remove the fuse that powers the supplemental steering control (3T3964).4. Turn on an accessory light (except cab dome light). If the accessory is dead, go to Step 6. If accessory turns on, disconnect switch is shorted. Continue with Step 5.5. At the disconnect switch, disconnect the cable routed from the frame of the product. (There are two cables at the disconnect switch. One cable connects to the frame, the other to the negative battery terminal.) Be sure this loose cable end cannot contact either stud on the disconnect switch. Diagnose and replace the disconnect switch as required.6. At the battery, disconnect the negative cable routed from the disconnect switch. When two or more batteries are involved, disconnect all negative battery terminal cables on all batteries that connect to one side of the disconnect switch.7. Complete necessary repairs to the system.8. Do Steps 2 through 6 in reverse.