right on RCAV8TOR,
by jumpering the coolant level switch, it caused the circle and exclamation mark. All makes react differently when plugs are undone. Some cause errors and other trucks may work fine. It`s like that with Nissan. Most trucks I work on would stop dead if you hit the brake switch. This one runs fine without any switch hooked up. That`s Nissan for you. Other trucks with low level switch broken are fooled by jumpering them, but this one doesn't like jumper. may need a certain resistance. P22 went away after spraying pins at ECM. All running good now, but have to do more work if the customer wants annual safety check!
Thank you all for the help!