Error Codes...Not Accessing?

[Challenger-II]

OK... . I've read the posts and cycled my key on/off in the described manner. All I get is my odometer mileage reading... . nada, zip! Is this what you should expect if there are no codes registered or will this method not work on my '99? :{

 

[KatDiesel]

I think it only works on the 2000 and up trucks. My 01 was built Feb 2000 and it works.

 

[rashwor]

'99 doesn't work.

My '99 was built in March 99 and it will not show the codes, but my wifes' 2000 will show the codes, so I know I have the technique down. I wonder if the dealer can do a reflash so that the '99s will do it???