Guide on Using CGDI CG100X or CG100 Prog III to Reflash BCM Lithium Battery Module
This guide explains how to restore the normal functioning of a Porsche Cayenne’s lithium battery using the CGDI CG100X or CG100 Prog III programmer. By following this process, you can disable the battery’s protection mode, which is activated during a severe accident or significant voltage drop, preventing the battery from charging and causing the vehicle to fail to start.
Why Does the Battery Enter Protection Mode?
When a Porsche Cayenne experiences a severe accident or the 12V lithium battery’s voltage drops too low, the battery enters protection mode, making it unchargeable. As a result, the vehicle fails to start, and replacing the battery becomes an expensive procedure.
How to Check Battery Voltage?
The front of the battery has a label with key parameters, such as capacity, voltage, current, and manufacturing date. Use a multimeter to measure the voltage if the battery is intact. If the voltage reads 0V, this indicates there is no output voltage, meaning the battery cannot be charged, and no current can enter it.
Step-by-Step Guide to Restoring the Battery
- Remove the Battery Cover
After removing the cover, measure the battery’s voltage again. If it still reads 0V, this suggests the relay is blocking the voltage. - Locate the IC Chip
Open the upper part of the battery case to find the IC chip, produced by Freescale, model SPC5644BMLU8. This chip controls the overall operation of the battery. - Role of BCM and the Relay
The BCM controls the battery relay, disconnecting it when the protection mode is triggered. This occurs in the event of an accident or low charge, preventing the battery from over-discharging, which could damage it. - Connecting CG100 Prog III
To repair the Porsche lithium battery, use the CG100 Prog III. Launch the CG100 software and select the appropriate options: BCM — Porsche — lithium battery — Cayenne — 2018 — SPC5644B. - Reading the Data
Connect the battery to CG100 using the BCM4+ adapter. Then, click «Read» to retrieve the PFLASH and DFLASH data. This process will take about 5 minutes; do not disconnect the device during the operation. - Saving and Writing Data
Save the original PFLASH and DFLASH data. Next, proceed to write the data: start with writing PFLASH, verify it, then write and verify DFLASH. The CG100 software will automatically handle these operations, which will take about 10 minutes. - Checking Voltage and Charging
After completing the repair, check the battery voltage using an external voltage regulator. During charging, measure the voltage using a precise regulated charger. - Final Steps
Charge the battery to the normal voltage of 12V and then disconnect the charger. Reinstall the battery and measure the voltage again, which should now read 11.92V, indicating a successful repair.
Conclusion
Using CG100X or CG100 Prog III allows you to successfully restore Porsche lithium batteries, ensuring their continued operation and avoiding costly replacements. For best results, it’s recommended to perform additional charging after installing the battery back into the vehicle.
