What is an APU board? (Hard and Race Drivin)

ronniep

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I have a RD cockpit and it is not working at all. The screen just scrolls drive over and over (using 3 different known working boards). If I unplug the apu board it seems like it loads the game, but sound is not working and nothing can be calibrated.

Does anyone know what the apu board does?

Thanks!
-Ronnie
 
hell i dont remember exactly... its audio but theres more to it than that.


first things first and youll think im nuts... replace all the fuses.

Ive had several issues with both my upright and cockpit due to low voltage, and most of the time it was traced back to voltage drop across a fuse... not blown, just dropping voltage.. so spend a few bux now just because...

also, measure ac voltage into your power supply, and the +5 voltage coming out and report back.
 
I'm not an expert on these but have worked on them and the "APU" board doesn't sound familar. Is it in the main stack of boards or mounted elsewhere?
 
That's the board that drives the steering motor isn't it? Check where the wires are going to. If so, from what I know it is a high voltage board and needs to be worked on with respect to the high voltage. Anotherwords, don't jack with it powered up. Does your steering motor have a belt drive or just one large motor directly attached to the steering wheel?
 
The APU board is not the steering board. If you look above the APU board mounted to the right of the monitor chassis you'll see the steering amplifier board.

The APU provides audio amplification for the speakers and AC power to the shifter board as well as provides a portion of the circuitry (a transistor and other stuff) for the seat magnet, wiring for the key switch, 12v to the coin door and a few other things.

It's basically a "there wasn't a better place to put this circuit so it went on the APU board" board, from what I can tell.

Also - measure your 5V from the test points on the main board, not directly off the power supply.

Edit: Look here for a schematic package. It'll help with tracing what goes to where. http://www.cityofberwyn.com/schematics/PDF/HardDrivinSchem.pdf
 
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Ok... I am starting to get somewhere, but still kind of stumped.

I have replaced all of the fuses on every board. I have measured the AC to the power supply and getting 120 v. I measured the DC voltage at the power supply and adjusted it to 5.05 V.

After a little troubleshooting and unplugging stuff one board at a time It seems for some reason my steering is not properly working (or working at all). I can boot the machine up with everything attached as it should be and it just scrolls "drive" on the screen. As soon as I disconnect the J11 pots c that seems to go to the steering motor or potentiometer it boots right up (no steering or sound though).

I still do not know where the problem lies, but at least I am narrowing it down. Any help would be greatly appreciated.

Here are the pics...

http://i545.photobucket.com/albums/hh394/bjinatj/forum pics/board.jpg

http://i545.photobucket.com/albums/hh394/bjinatj/forum pics/screen.jpg
 
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That's the board that drives the steering motor isn't it? Check where the wires are going to. If so, from what I know it is a high voltage board and needs to be worked on with respect to the high voltage. Anotherwords, don't jack with it powered up. Does your steering motor have a belt drive or just one large motor directly attached to the steering wheel?

the steering motor ppcb is a different thing, and its mounted on a big metal heat sink/plate
 
I will try that right now and update you right away. I also have another power supply that I might be able to try (if it works).
 
Ronnie: you mentioned that the game boots into test mode. Race Drivin' has an extensive set of testing software built in. Did you test *everything*?

If everything test correctly, there's a good chance you have an issue with one or more of the EPROMs.
 
Ronnie: you mentioned that the game boots into test mode. Race Drivin' has an extensive set of testing software built in. Did you test *everything*?

it will boot into test mode and do it's initial test. If I hold the key and go into the advanced it will bring up the menu, but as soon as I select anything it will reboot back to the menu. It will not let me actually run anything beyond the initial self tests. This happens with 2 RD boards and a HD board.
 
This is upsetting. This is the only game I own and the family is coming over to Easter tomorrow. Everyone was looking forward to playing it. Oh well.. I will get it fixed and still be able to enjoy it for myself anyway..
 
Measure the ohms on the steering pot with a multimeter. Make sure you don't have a short.

Now you are getting over my head. I know what the ohms symbol looks like and I am sure I could do this. There are three wires (red, black and bare). I assume I am measuring the red and black?
 
For some reason it will now boot up with j11 connected, but I cannot calibrate anything. Steering no longer works and the shifter as well.
 
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