The simplest way to tell about the harness is to view the single ground wire that goes down the center middle of the intake. Most of the other wiring is securely sealed. Too bad they didn't make the wire insulation out of the same tough material as the shielding.
If you go beyond the harness there is a lot of info on the code 19 problems in the archives. One should also check the individual control units for codes (see the article in DIY section or archives for procedures). You have pulled codes from the Diagnostic Module (DM), you also need LH (fuel control), DI (ignition), EA/CC/ISC (electronic accelerator/cruise control/idle speed control) and possibly the base module (control unit UPS/power supply module)
Bosch Master, ASE Master, L1
33 years MB technician