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Out of curiosity, but has anyone here had to replace their BCM connector at all? Or better yet - replace the terminals/pins within the connector?
The previous owner of my 2004 E320 never replaced the third brake light, which is notorious for allowing water to leak into the trunk. The water pools up on the plastic cover/trim right above the BCM, which of course passes over the BCM and its associated connector. After disconnecting the connector, I was able to clean the pins on the BCM itself but don't really have any way of cleaning up the terminals since the ports are so tiny on the connector. This is a Minnesota car that's seen salt/snow it's whole life, so the water that made its way in through the third brake light was frequently salty water (the worst).
TLDR; "Battery Protection Conven. Functions Temporarily Unavailable" displays on the dash very randomly - such as after driving for 20 minutes, and then goes away after turning the car off and then back on again. Reading voltage from the gauge cluster, the battery shows 12.5ish volts (going off of memory) while powered off, and shows 14 volts while running - indicating that it's properly charging. Voltage regulator, main battery, aux battery, and BCM relay have all been replaced recently - so I suspect the BCM is probably giving me trouble, with a clean connector seeming to be the next easiest "potential fix" prior to further diagnosing.
06-29-2023, 10:38 PM
BCM Connector Replacement - water/corrosion
