TOD Check light flashing Mechanic says 3 Grrr

[Thelgord]

According to the shop manual, the EHCU (Electronic Hydrolic Control Unit), if bad can send an error to the TOD computer on pin 9 (on the EHCU) and cause the Check TOD error light. The sensor for the TOD unit is most likely the transfer case shift position sensor. Either one will cause the light. The shift position sensor for the TOD computer is probably the culprit, and the cheapest part to change. It is on the transfer case.

Or I'm completely wrong. But if there is a bad TOD sensor, I would change just that first and see if light goes out.