Before the PL522 or 523 is replaced, ensure that replacement is necessary. The PL522 or 523 is seldom the cause of a fault. Always check that power is available to the PL522 or 523. Battery voltage is required between contacts 1 and 2 of the machine harness connector for the PL522 or 523. Continue ONLY if all other attempts to isolate the problem have failed. Always consult your dealerships Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce the time that is required for a repair.
- Turn the disconnect switch and the key start switch to the OFF position. Disconnect the machine harness from the PL522 or 523.
- Remove the PL522 or 523.
- Ensure that the replacement PL522 or 523 kit is the correct part number.
- Install the replacement PL522 or 523 system according to the Special Instructions that are included in the installation kits.
- Flash the software to the new module in order to ensure that the latest version of the software is on the system.