2010 X5 35d - won't start after injector replacement

[torqueisking]

I fixed it...fixed it real good.

After the injector replacement, the only issue was it wouldn't start but cranked normally.

I electrically checked every fuse and relay including the fuse pack next to the DDE, under the glove box, and back right side. No problems found.

I tried to start it again and it now won't crank. Idrive screen is dead. Dash lights up with DSC, ABS, 4x4, air bags, transmission failure messages. INPA comes back with 22 error codes from JBB, MRS, DDE, EMF, CAS, KOMBI, PDC, FRM, etc.

Likely safe to say all those modules are not damaged. A similar group of seemingly unrelated errors appears when my engine-to-chassis ground corroded away.

Looks like a battery issue but the battery is in great shape. It's been on a trickle charger since the injector episode started. Just to cross it off the list, I connected my fully charged roadside starter battery and tried to start it. No change.

Disconnected the battery/charger, shorted the vehicle +ve and -ve, waited a few minutes, power reconnected, no change. Tried this three times.

Rechecked every fuse, connector and relay that I touched. Nothing found, errors still there with no cranking.

Next troubleshooting steps including testing CAN connectivity/operation, supply voltage, and ground at each module...after I find them.