I was hoping for some help for this aggravating problem. Just had the transmission rebuilt and replaced in my 2002 Isuzu Axiom and the Check TOD light started flashing. Transmission guys were clueless. Found some help on planetisuzoo.com and took the suggestions to our local mechanic. Speed sensor wasn't it. He finally got a 17 code (not on computer) and tried replacing the range mode switch assembly. Nada. Just got the dang thing back today. Transmission is leaking fluid, so back to transmission guys, but the TOD light is still happily flashing. I'm thinking wire cutters, or black electrical tape over the light. 4H and 4L seem to work fine.