[mfortune042]

This sounds like a BPGA fault. The BPGA is often called a battery protection unit. This is the fusebox that sits on the battery and includes a relay. This is a safety device that disconnects the power to a large number of the car's modules about 20 minutes after the car is turned off. When the doors are unlocked it should turn the power back on but the relay sometimes fails. On the early BPGAs you could replace the relay module on later BPGAs you have to replace the whole fusebox. I think the 508 has the later type of BPGA. I attached some details on the 508's BPGA.

There are lots of complaints about the BPGA on the forum. The first thing people notice is that when they unlock the doors the mirrors fail to deploy. Sometime if you disconnect and reconnect the battery you can get the relay to close.

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