Ridge Racer Accelerator Potentiometer

[fatsgt]

I just picked up a Sit Down Ridge Racer Machine.  The game is started by pressing the gas pedal but nothing happens which likely means there is an issue with the pot.

I took the assembly out and this is what it looks like: 



I assume the first thing I would want to do is check the voltage on the Potentiometer to  make sure I'm getting 5V. There are three wires coming from it, what combination should I choose to check it with my voltimeter?  (Sorry, very new at this)

Second question, if I need new pots, which ones should I order and who has the best prices? The manual says "Accelerator/Brake Control Pot (5k) 76000652" but I haven't been able to locate it with that part #.

Thanks folks!

[Paul Olson]

The two outside wires are 5v (red/white) and ground(probably black/white, but I can't see in the pic). Black lead on the black/white wire, and the read lead on the red/white wire. That should read right around 5 volts.

Once you have varified that you have 5v going to the pot, you can move the red lead to the middle wire. The voltage reading there should travel between 0 and 5 volts as you turn the pot.  You will have a somewhat limited travel due to the range of the pedal, so you will only see part of the 5 volt range. The main thing you are checking is that the value is changing as the pot is turned.

If the pot seems to be working, trace the middle wire to the board and make sure that you read close to the same voltage at the board. If not, the problem is somewhere between the wire and the board.

If the voltage is getting to the board fine, the pot may need to be adjusted. The pedal may not be be moving the pot far enough for the game to register a full pedal press. I think there is a test menu on Ridge Racer (not sure though, I sold mine about 5 years ago, so the details are a little fuzzy). You can look at the throttle input there to see the range in hexidecimal. You will probably need to find a manual to see what the range is supposed to be though.

If you need a new pot, I think you can get them from Happ still, but they are around $25 each. Radio Shack may have some that will work, but you may have to cut the shaft to make it fit. Probably the best bet is to put a wanted post up here and at KLOV to see if anyone will sell you a spare.

Also, it looks like it is probably fine, but I can't tell for sure in the pic, but make sure the lugs from the pots aren't touching the metal frame.

[fatsgt]

Thanks! What setting should my multimeter be set at to test if it's getting the 5V?  Should the machine be on or off?  Ugh, confused.

[Paul Olson]

Set it to DC voltage. If your DMM is not auto ranging, set it to the lowest setting that is above 5 volts (it will probably be 20v). The machine will need to be on to get the 5v to the pot.

[fatsgt]

OK, so using my Multimeter, with the machine on, I put the red lead on the red/white wire and black lead on the black.white wire... No reading.  I also had someone hold down the pedal... No reading.  I was doubting that I was using my volt meter properly so I tested in on a coin door light and it read 17V. 

So if I tested correctly, there is no power making it to the pots correct?

[Howard_Casto]

Yeah that's a problem. 

[fatsgt]

Ugh, A bad pot was what I was hoping for. So this means I need to get in the guts of this thing and test what's going on at the board correct?  It's late and I'll check tommorrow but I don't think it's going to be an easy task getting into that board.   

[Howard_Casto]

What I would first do is trace all those wires back and test them at the board.  It might be as simple as a bad wiring harness, which should be easy enough to fix. 

[fatsgt]

OK, So I'm trying to figure out why I have no voltage to my pots.  I checked the molex connector that goes to the pedal assembly.  It appears to be secure.  Looking into the cab where the pedals were removed I see two connectors that are not plugged in. 

Maybe they're not used?  Its a small space and I don't see any logical place for them to connect to.

[vandale]

OK, So I'm trying to figure out why I have no voltage to my pots.  I checked the molex connector that goes to the pedal assembly.  It appears to be secure.  Looking into the cab where the pedals were removed I see two connectors that are not plugged in. 

Maybe they're not used?  Its a small space and I don't see any logical place for them to connect to.

leave those well alone. If the game displays on screen and audio is working then leave all power wires alone.

As mentioned by others earlier, I would trace the pots back to the io board or game board and check voltage at each connector

[fatsgt]

SUCCESS! 

I pulled the connections off the board.  The seating of some of them were questionable, especially a coupling for a single green wire which was possibly the ground for the controls. 

After fiddling with the settings and calibration it's totally playable! 

Thanks so much for your help. Turning out to be a nice $96 investment. 

I still have some ugly graphic issues but I'll post those in a different thread.  Again, THANKS!

[BadMouth]

 

[Howard_Casto]

Glad you got it sorted, but just for future reference the FIRST thing you try is to re-seat all the connections. 

[fatsgt]

lol, rodger that!

[Paul Olson]

Glad you got it sorted, but just for future reference the FIRST thing you try is to re-seat all the connections. 

I thought about this as I was typing earlier, but figured that it would be easy to start at the pots since you already had them removed. Glad to hear you got it working. I miss my Ridge Racer sometimes, but that is just too big of a game!

[fatsgt]

Well Paul, if you have any suggestion on how to fix my video glitches now I'm all ears.  

[Paul Olson]

Well Paul, if you have any suggestion on how to fix my video glitches now I'm all ears.

Try reseating all of the eprom chips. Be careful not to damage the legs. If that doesn't fix it, one or more of the rom images may be corrupted. You can order replacements from hobby roms if you need to. They are pretty easy to erase and burn new images on, but it requires a rom burner and a UV eraser. If you have a rom burner, you can compare the rom images against the mame set to see if it is corrupted. I don't remember if Ridge Racer used a hard drive, but the hard drive could have corrupted data as well. Sometimes, just pushing on an eprom can affect the glitch if it isn't properly seated, so maybe try that before removing them if you have someone who can watch for any changes when the glitches are happening.

Also, try reseating any of the connectors that you haven't yet reseated.

[fatsgt]

Well Paul, if you have any suggestion on how to fix my video glitches now I'm all ears.

Try reseating all of the eprom chips. Be careful not to damage the legs. If that doesn't fix it, one or more of the rom images may be corrupted. You can order replacements from hobby roms if you need to. They are pretty easy to erase and burn new images on, but it requires a rom burner and a UV eraser. If you have a rom burner, you can compare the rom images against the mame set to see if it is corrupted. I don't remember if Ridge Racer used a hard drive, but the hard drive could have corrupted data as well. Sometimes, just pushing on an eprom can affect the glitch if it isn't properly seated, so maybe try that before removing them if you have someone who can watch for any changes when the glitches are happening.

Also, try reseating any of the connectors that you haven't yet reseated.

OK, I have all the boards pulled.  Thought I would check the power supply voltages first.
Outputs should be +5, -5, and 12.
With my meter on DC I'm getting +2, -2, and 9.
There's an adjustment on the outside that made the fan go higher but did not effect the voltage.
I'm guessing I need a new power supply?

[Paul Olson]

Make sure you test the power supply voltages with some kind of load. The game running would be a good load on it. The switching power supplies need to have some load to operate properly. Those numbers can't be right, because we know that your game booted just fine, and there is no way it would boot with only 2 volts powering it.

[fatsgt]

Thanks Paul.  I guess I'll put everything back in the Cab then.   I was checking the voltage on the molex connectors.  When I have those connected where is the best place to check the voltages for my poser supply?

[fatsgt]

I'm getting this error when testing the boards:

[img=http://s27.postimg.org/pbvd077cf/photo_2_6.jpg]

"Point ROM Error"?

[fatsgt]

Did some research and the the point rom is a separate board.  They go pretty cheap on ebay for an untested ones. http://www.ebay.com/sch/i.html?_trksid=p2054897.m570.l1313.TR0.TRC0.H0&_nkw=NAMCO+SYSTEM+22+POINT+ROM+&_sacat=0&_from=R40

Would be nicer to get a tested working one so maybe I'll post a wanted add here.  Since they are listed "System 22" and not game specific I'm guessing these are standard to all System 22 boards?