Over the years I've had a few issues with these controllers & most important is having the correct Calibration/O.S. for the service/part number & same as all other controller programming a good power source for controller & laptop/programming device, but even if all that is correct there can be other issues that may cause program to fail in a write & controller will become unresponsive...
So after having a controller on the bench for a week & went through all the key's for seed from 0000 to FFFF & not finding key, I went & tried to listen to & send commands to controller & soon realized it wasn't doing anything! (hindsight I should have done this before key search)....
I then went back to what I looked into years ago & tried to find info for BDM/JTAG read & can't find anything but know there is people out there with a lot more info & images but are waiting for the right reason/circumstances, but this is what I know so far...
It seems to be a Delphi with IBM(PowerPC) MPC561 & this is the case taken off & rear of PCB...
I was able to borrow a friends tool to get info on what to connect to to get the file done on the bench, but seeing the E38 has the main components on the side of the PCB not shown &/or easy to remove from case it's hard to know where to connect but this is the closest info that I believe may be to get info on/off over bench...
Now after going through all that & wasting a week or so(but would still like to find out how to do it for future reference) I eventually thought I have no other options so had a good E38 controller here & made some modifications to the wiring connector to make a quick swap harness, I used the good controller to set write entire & as soon as the unlocking controller message came up I swapped the harness from good to bad PCM & had just gone to programming mode & after 5 minute or so write process it was back to life although it showed weird characters for VIN & Serial but then did a write VIN section by itself seperately & all back to normal.. WOOHOO!
