Additional information incase anyone comes to this in a search:
Total bill was $670 from the dealer.
$30 Shop supplies
$70 Re-key to use existing keys
End result is the new cylinder seems "notchy" presumably due to the key being slightly worn and the lock being new. Since the ignition was stuck in the "On" position, the battery drained completely.
When I picked up the car, the service department was closed, and there was Er IU on the trip odometer. Cruise control would not turn on.
No CE light or codes.
Reset ECU, error didn't clear.
Disconnected battery positive terminal
Depressed brake for 10 seconds
Reconnected battery positive terminal
Turned ignition switch to ON for 30 seconds, letting the BIU fully boot (according to another article)
No error, cruise works.
Cancelled the appointment and left a message for the service manager with the fix (he hadn't seen this trip odometer error code before).
Alternate search terms:
ER1U, ERIU, ER 1U, ER IU, Ignition lock, key stuck, won't start battery good
No, the name has nothing to do with bragging about 20 inch wheels...