2003 Adventurer electrical or computer problem

[Don Noris]

I recently took my 2003 Adventurer into a collision repair shop. It had set for about 3 months in storage. I could not go out and start it during storage. I jumped it and it started fine. Then I drove it about 15 miles to the repair shop. I went in and gave them the keys, filled out the paper work. As we were leaving they moved it, started right up. Then a week later they said that they had to jump it to get it started and it would not even turn over. It displays this code: PRND321, on the main line it is : NO J1850 ACTIVITY. Then they had an outside mechanic look at it and now they want $500.00 to rebuild the computer, or $1100 for a new one. I personally think that when they jumped it they did not hook it up right and may have messed up the computer. I am afraid that if I have them put in a new computer that it still would not fix the problem.

Please help, does anyone know what this code means?

Any advice as to whether I should get a new or rebuild the computer?

Thanks in advance.