Error code 64 on a 93' Aerostar

I have a 93 ford aerostar xl, 3.0 engine with 105,000 miles on it.
It was running a little rough the past week or so and just died while I was driving the other day.
Everything electrical seems fine, cranks but will not start and I can hear the fuel pump turn on.
I ran a poor mans diagnostic test a I believe the code I was given was 64.
I've been surfing for a while and found the results to the code, the problem is that it's not exactly english to me and I'm not sure what I have to do to fix this problem.
What I recieved is " 64-IAT indicated 123 C (254 F) I circuit grounded."
What's the solution?
I greatly appreciate any input
Thank you
R