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Picked up a CEM on eBay specifically to destroy it (carefully)... For science! Will eventually correlate this with the design/function info from ViDA, but for now, enjoy the pictures :beer:
Top of CEM (when installed in vehicle) - this is the power board side.

Bottom of the CEM (when installed in vehicle) - this is the logic board side.

ITS A FORD?!1?/!?>

jk
Fuses and relays removed.

The best way to open this case without breaking anything is to carefully disengage one locking tab at a time with a thin spudger (or screwdriver) and insert a zip tie such that it can't re-lock. Once all tabs are shimmed out, the case will just fall apart.

Bottom of case removed, exposing logic board. There is a small power board structurally attached with jumpers for the Floor-1 connector, presumably due to limitations on their pick-and-place or reflow setup (or cost savings by reducing multilayer footprint, or for better noise isolation).

Close up of logic side, still in case. This is a 4 or 5 layer PCB with a conformal coating, making following traces and identifying components a huge pain (see below).

Power side, removed from case. Note there are 5 different, non-replaceable mechanical relays (in addition to the two replaceable relays R15 and R16). This is a 2 layer (top and bottom) PCB making it super easy to follow traces. There is no conformal coating, and all contacts are tin plated as would be expected for an interior component (opposed to Ag/Au found in corrosive environments like the engine bay).

The complete CEM internal assembly. No additional fasteners or fly leads - it's self supporting including all electrical contacts. The upper and lower halves are structurally connected using thick jumpers which provide the majority of the support in both compression and tension. There is a plastic spacer which provides additional compression strength towards the center for better rigidity.

Closeup of sandwich assembly, including insulator/spacer.

Reverse of logic board, with attached power connector.

Reverse of power board.

All the parts are belong to us. Yep, this CEM isn't going back together

Logic board isolated.

Neither heat nor solvent would affect the conformal coating, so I resorted to good-old-fassion scraping away. Several hours later, I was able to expose and identify all of the major components (click to enlarge!!):

CPUs
NXP MC9S12DG256 @ 4 MHz (2 CAN modules) -> low speed only
NXP MC9S12DT256 @ 8 MHz (3 CAN modules) -> high speed and low speed
Dual Inline
1 - Infineon BTS443P 25A Smart Highside Power Switch
2 - Infineon BTS724G 4 x 3.3A Smart High-Side Power Switch
3 - Infineon BTS5210G 2 x 2.4A Smart High-Side Power Switch
4 - Infineon TLE4269 5V 150mA Automotive Qualified Regulator
5 - Infineon TLE4299 3.3V 150mA Automotive Qualified Regulator
6 - ON Semi MC14538B Dual Precision Retriggerable/Resettable Monostable Multivibrator
7 - NXP MC33399 LIN Physical Layer Interface
8 - NXP TJA1040 CAN Physical Layer Interface
9 - NXP HEC4013B Dual D-Type Flip-Flop
10 - NXP HCF4081 Quad 2-Input AND Gate
11 - ST Micro L9823 Octal low-side driver for bulb, resistive and inductive loads with serial input control, output protection and diagnostic
12 - ON Semi MC74HC4851A Octal analog mux/demux with injection current effect control (Automotive)
SOT
1 - BCP53 -1.2A PNP GP Transistor
2 - Infineon BSP78 3A Smart Low Side Power Switch
3 - BCP55 1.5A NPN GP Transistor
4 - Infineon BSP75N 1A Smart Low Side Power Switch
Top of CEM (when installed in vehicle) - this is the power board side.

Bottom of the CEM (when installed in vehicle) - this is the logic board side.


jk
Fuses and relays removed.

The best way to open this case without breaking anything is to carefully disengage one locking tab at a time with a thin spudger (or screwdriver) and insert a zip tie such that it can't re-lock. Once all tabs are shimmed out, the case will just fall apart.

Bottom of case removed, exposing logic board. There is a small power board structurally attached with jumpers for the Floor-1 connector, presumably due to limitations on their pick-and-place or reflow setup (or cost savings by reducing multilayer footprint, or for better noise isolation).

Close up of logic side, still in case. This is a 4 or 5 layer PCB with a conformal coating, making following traces and identifying components a huge pain (see below).

Power side, removed from case. Note there are 5 different, non-replaceable mechanical relays (in addition to the two replaceable relays R15 and R16). This is a 2 layer (top and bottom) PCB making it super easy to follow traces. There is no conformal coating, and all contacts are tin plated as would be expected for an interior component (opposed to Ag/Au found in corrosive environments like the engine bay).

The complete CEM internal assembly. No additional fasteners or fly leads - it's self supporting including all electrical contacts. The upper and lower halves are structurally connected using thick jumpers which provide the majority of the support in both compression and tension. There is a plastic spacer which provides additional compression strength towards the center for better rigidity.

Closeup of sandwich assembly, including insulator/spacer.

Reverse of logic board, with attached power connector.

Reverse of power board.

All the parts are belong to us. Yep, this CEM isn't going back together

Logic board isolated.

Neither heat nor solvent would affect the conformal coating, so I resorted to good-old-fassion scraping away. Several hours later, I was able to expose and identify all of the major components (click to enlarge!!):

CPUs
NXP MC9S12DG256 @ 4 MHz (2 CAN modules) -> low speed only
NXP MC9S12DT256 @ 8 MHz (3 CAN modules) -> high speed and low speed
Dual Inline
1 - Infineon BTS443P 25A Smart Highside Power Switch
2 - Infineon BTS724G 4 x 3.3A Smart High-Side Power Switch
3 - Infineon BTS5210G 2 x 2.4A Smart High-Side Power Switch
4 - Infineon TLE4269 5V 150mA Automotive Qualified Regulator
5 - Infineon TLE4299 3.3V 150mA Automotive Qualified Regulator
6 - ON Semi MC14538B Dual Precision Retriggerable/Resettable Monostable Multivibrator
7 - NXP MC33399 LIN Physical Layer Interface
8 - NXP TJA1040 CAN Physical Layer Interface
9 - NXP HEC4013B Dual D-Type Flip-Flop
10 - NXP HCF4081 Quad 2-Input AND Gate
11 - ST Micro L9823 Octal low-side driver for bulb, resistive and inductive loads with serial input control, output protection and diagnostic
12 - ON Semi MC74HC4851A Octal analog mux/demux with injection current effect control (Automotive)
SOT
1 - BCP53 -1.2A PNP GP Transistor
2 - Infineon BSP78 3A Smart Low Side Power Switch
3 - BCP55 1.5A NPN GP Transistor
4 - Infineon BSP75N 1A Smart Low Side Power Switch