1995 Ford F-150 Diagonostics Codes

Computer problem
1995 Ford F-150 V8 Four Wheel Drive Automatic

I've done a diagonostics code check on the engine the code that comes up is 21 and when I looked up the code number to find out what it is it says ECT out of Self-Test range MAP/BARO out of Self-Test range. I'm not sure what this means. I was wondering if you could tell me what this means and what exactly it is that I need to fix or replace on the engine.