As you might guess, I think the plusses of the computers outweigh the minuses. On a non-computer tractor when things don't work you have to think through all the mechanisms that would cause the tractor to stop and then look at the various switches and sensors to see which one was bad. You'd look at the service manual and wiring diagram and figure out what to test.
The same procedures work on a computer tractor but you also have the option of being able to see these sensors electronically. I just had the fuel shut off solenoid go in my Kubota
B21. Between the service manual and great TBN help got it going. A computer tractor that could look at the solenoid and see if it was open or shorted to ground could have given me an error code that would have saved time. Better still it could have a bigger display and just tell me without some silly error code.
I am slightly annoyed on my JD4520 that they skimped on the user display. A small 64 x 128 dot graphics display is cheap. That would have let them say what was wrong instead of just an error number. So when a light bulb goes out (yes, computer tractors can sense that) it could tell you what the problem was. This would also let you figure out if you should continue working or if the error was serious enough to stop the work.
In a similar light, Deere should print all of the error codes in the user manual. It's annoying enough that the manual isn't free (in electronic form where there is no cost to produce it). If they did this as a trick to get people to buy the manual, well, surely the founders of the company would be spinning at 2600 RPM in their grave at such tactics.
Modern cars are a good analogy here. I know lots of people don't like the computers in them, but the ability to plug in a diagnostic plug and have some test equipment tell you what's wrong can often save time and trouble. It's a bad reality of modern life that if something is done to save time when servicing equipment, the end user will not see a lower cost, the dealer just gets more profit. Only the US with it's warped financial sector could call this improving productivity. But in the long run quicker and more accurate diagnosing is a win for everyone.
The only down side I see to computers is something no one will know until 15-20 years from now. Many of the parts on the circuit board will not be available in 15 years, so making exact replacements will not be possible. But it is quite posable to make a new board that has the same connectors and runs the same packet protocols on the CAN bus. By analogy, if you get a new computer you can still use the web because the data protocols don't change. If Deere wishes to keep it's reputation of having parts around for older tractors, they will figure this out. If they hire too many managers from the financial sector they will have an "it's out of warranty and not our problem, every computer failure is an opportunity to sell a new tractor" mindset and the company will go away. Having replacement controllers available for computer tractors is _not_ a technical problem, it's a managerial one.
A fun exercise for a future post is to look at all the signals going in and out of a controller- they are all pretty universal to all tractors. But I've gone on enough. Dcyrilc, it is at least a good thing that at this point in time the buyer can choose so to each their own. Just like in cars, I can't see the computers going away because of their emission control benefits, user features, and servicing benefits. There is definitely a right way and wrong way to computer control stuff as the auto industry took 20 years to figure out. The automotive industry has also advanced the technology of making electronics that work in the harsh environments that cars and tractors are in. Hopefully the tractor crowd can pick up on the automotive sectors learning curve without repeating the errors.
Pete
