Replace the On-Board Charger (OBC) Module

Safety Warning: This procedure involves high-voltage electrical components. High-voltage systems must be de-energized by a certified technician before proceeding. Do not attempt this repair unless you are a qualified EV service professional.

1. De-energize the high-voltage system by removing the high-voltage service plug and verifying zero voltage using a calibrated high-voltage multimeter.
2. Disconnect the 12V auxiliary battery negative terminal to prevent accidental system activation.
3. Drain the vehicle's cooling system as the OBC is integrated into the thermal management loop.
4. Remove the high-voltage cables and low-voltage communication connectors attached to the faulty OBC module.
5. Unbolt the module from the chassis mountings and carefully remove the unit from the engine bay.
6. Install the new OBC module, ensuring all high-voltage connections are torqued to the manufacturer’s specifications to prevent arcing.
7. Reconnect the low-voltage communication harness and the cooling lines.
8. Refill the cooling system and perform a vacuum bleed to ensure no air pockets remain.
9. Reconnect the 12V battery and use a high-voltage diagnostic scan tool to clear the C1A40 error code.
10. Verify the repair by initiating a Level 2 AC charge cycle and confirming the charging port indicator transitions to a solid charging light without error.

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