HiCustomerand welcome to JustAnswer,
Yout 1996 Toyota Avalon should be equipped with the OBDII connector. Where is this connector you're speaking of?
Does the connector look like this?
yes it has an connector under the dash and in the engine compartment and no it doesn't look like a OBD l or ll connector it's round and has 17 pins I've attached an pic of the cap not very good but you should get an idea of what it looks like
Thanks for the update with picture.
That connector is used for the ABS system. You need to look behind the fuse panel on the lower, left of the dash. There should be a rectangle panel that you pull off and the fuse block and OBDII connector will be there behind it. It's there, trust me.
The only idiots out there are the ones that don't ask the questions.
Happy I could assist you. Thanks for using JustAnswer.