Roy, since this ecu is in limp home mode, you must be able to read one (or more) troublecodes. So, first thing is to get the codes read. A simple led-tester will do that, but you can also use a star-tester. Then you know which circuit (doesn't have to be the sensor itself, can be wiring loom also) is causing the problems. Saves you a lot of time searching and trying.
Other way of testing is using a break-out-box and checking the signals with a DVOM.