Pole Position : no acceleration .. Gas pedal not responding

Pin 5 and 6 both stay solid low when i turn the game on and stays that way. I set logic probe on a leg..turn game on and instantly is low...not even a glimmer of a change.

I also switched the game to test mode with the logic probe on the pin and nothing changed. I also started a game, and same results.

I did this for 5 and 6 individually.

Then for shits and giggles i put logic probe on back side of edge connector to black wire...it beeped low...i press the pedal...it stays low...i put logic probe on tab with black wire on pot...stays low.

Then i put logic probe on back side of edge connector to red wire and it stays high....i press pedal, and stays high, i put logic probe on pot tab which red wire soldered to and stays high when i press pedal.

Shouldnt probe change from high to low or visa versa at edge connector or pot when i press pedal?

(I did do these edge connector and pot tests with the game coined up to qualify)

So i have a high (red wire) and a low (black wire) signal going to F of edge connector.

The probe detect state changes by reading voltage, kinda. Anything below 2.5 or so will be considered low by the logic probe. Anything above 2.5 will be considered hi by the logic probe. Depending on how you have that pot set it may never climb above 2.5 VDC which is why the probe stays low even when you operate the pedal.

Now, onto the heart of the matter.

GASEL should change state when the game is started or put into test mode. Since its not lets look at where GASEL comes from...

GASEL looks like it comes from pin 7 of 8E. Check it there to see what its doing when the game is in test mode.
 
The probe detect state changes by reading voltage, kinda. Anything below 2.5 or so will be considered low by the logic probe. Anything above 2.5 will be considered hi by the logic probe. Depending on how you have that pot set it may never climb above 2.5 VDC which is why the probe stays low even when you operate the pedal.

Now, onto the heart of the matter.

GASEL should change state when the game is started or put into test mode. Since its not lets look at where GASEL comes from...

GASEL looks like it comes from pin 7 of 8E. Check it there to see what its doing when the game is in test mode.

8e pin 7 stays low in test mode when gas pressed and when coined up and gas pressed....zero fluctuation.
 
On Chip 8E, you'll need to check Pin 7 to see if it's pulsing. If it's not, then you should check pins 1, 2 and 3 of 8E. If they are all HIGH then 7 should be High, if any of them are Low then 7 should be low.

If 1, 2 or 3 never change states, then you need to follow that back to either 7J/7K or 6J depending on the pins.

EDIT: this is wrong, I read the datasheet wrong.
 
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On Chip 8E, you'll need to check Pin 7 to see if it's pulsing. If it's not, then you should check pins 1, 2 and 3 of 8E. If they are all HIGH then 7 should be High, if any of them are Low then 7 should be low.

If 1, 2 or 3 never change states, then you need to follow that back to either 7J/7K or 6J depending on the pins.

In attact and coined up pins 1,2 and 3 of 8e are high with a pulse...pin 7 stays high, no pulse. I also pressed gas pedal and nothing changed.

Which is odd because in my earlier post 30 minutes ago i tested pin 7 and it was low with no pulse? Did I accidentally test pin 8 earlier because that is low with no pulse right now......damn..im almost positive i tested pin 7 earlier.
 
Would any of the customs be part of the gas? I did recently have 3 of them replaced...i dont know which 3 were replaced...i just sent an email inquiring which 3 were swapped out.
 
Would any of the customs be part of the gas? I did recently have 3 of them replaced...i dont know which 3 were replaced...i just sent an email inquiring which 3 were swapped out.

I would think that if any of the pins in 1, 2, or 3 pulsed then you should see a change on Pin 7 unless I'm reading the datasheet wrong.

What are pins 13 and 14 and 15 doing on 8E?
 
Yes, I did read it wrong...

74LS259+Diagram.png


Looking at that pin 7 is Q3, which is enabled by pin 1 being High, pin 2 being High and pin 3 being Low.

If pins 14 and 15 are High, then you should get output on pin 7.

Might be tricky to test as you have to figure out if both 14 and 15 are high at the same time.

Not sure what the "Each Other Output" means. Maybe that if 14 is Low and 15 is High you'll also get something on pin 7.
 
Testing pin 2 of chip 6h...pin 2 of 6h is listed as ABEnable...and the manual states that if no gas to check AD converter......i am just assuming pin 2 enables the ad converter...is that correct?

https://youtu.be/02uPM8tqBzE
 
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Yes, I did read it wrong...

74LS259+Diagram.png


Looking at that pin 7 is Q3, which is enabled by pin 1 being High, pin 2 being High and pin 3 being Low.

If pins 14 and 15 are High, then you should get output on pin 7.

Might be tricky to test as you have to figure out if both 14 and 15 are high at the same time.

Not sure what the "Each Other Output" means. Maybe that if 14 is Low and 15 is High you'll also get something on pin 7.

14 is pulsating hi...15 is solid hi....7 is now solid low.......in the last two hours pin 7 is testing either solid hi or solid low ..(solid meaning no pulsing or beeping..its a solid steady tone)

Its the same in attract or coined up.
 
14 is pulsating hi...15 is solid hi....7 is now solid low.......in the last two hours pin 7 is testing either solid hi or solid low ..(solid meaning no pulsing or beeping..its a solid steady tone)

Its the same in attract or coined up.

Well, that's good. So you said that pins 1, 2, and 3 are pulsing? (you said High with a pulse, not sure if you mean they are pulsing)?

If they are pulsing then I would suspect 8E as bad. If they are not then maybe an issue with 6J.
 
Well, that's good. So you said that pins 1, 2, and 3 are pulsing? (you said High with a pulse, not sure if you mean they are pulsing)?

If they are pulsing then I would suspect 8E as bad. If they are not then maybe an issue with 6J.

What about my previious test i posted about of 6h, pin 2?
 
Testing pin 2 of chip 6h...pin 2 of 6h is listed as ABEnable...and the manual states that if no gas to check AD converter......i am just assuming pin 2 enables the ad converter...is that correct?

https://youtu.be/02uPM8tqBzE

Can't say what enables the AD, but it doesn't matter since nothing is getting into the AD in the first place. If pin 6 of the 8J never changes your input is missing.

Since pin 6 of 8K is not pulsing 8K never outputs anything to 8J.

Pin 6 of 8K is controlled by pin 7 of 8E. Based on your testing it looks like something is going into 8E, but nothing is coming out of it. So I would replace 8E first.
 
Youtube link below of leg testing with game in attact and game play.

Testing a swapped out 8e...i took a 74259 off of a ms pac board from location 8k...it was the only 74259 on the board and again, i have never seen this ms pac board work so i can only assume its a good chip.

I did socket it onto the pp

Please bear with the video..its 9 minutes long..i was having positioning problems...my work area is very cramped and me repositioning is what extended the video....and btw, no luck...still no gas.

Does 8f, 6m or 6l need to be tested?...those are part of the gas pedal matrix.

https://youtu.be/7jygB-n4lwY
 
Pole board failure

Watched your vid. For test purposes instead of keep on coining up+getting pissed off , why don't you set the dip switches to free play. It will keep playing over + over saving you time till you figure it out.
 
Youtube link below of leg testing with game in attact and game play.

Testing a swapped out 8e...i took a 74259 off of a ms pac board from location 8k...it was the only 74259 on the board and again, i have never seen this ms pac board work so i can only assume its a good chip.

I did socket it onto the pp

Please bear with the video..its 9 minutes long..i was having positioning problems...my work area is very cramped and me repositioning is what extended the video....and btw, no luck...still no gas.

Does 8f, 6m or 6l need to be tested?...those are part of the gas pedal matrix.

https://youtu.be/7jygB-n4lwY

Ok, we don't want to worry about 8F, 6M, or 6L until we figure out why you're not getting anything out of 8K.

If you're not getting anything out of 8K, nothing downstream can be trusted as accurate.

Since 8E seems to be OK, then we need to check pin 1 and 12 of 6K and 1, 4, 7 and 9 of 6J.

EDIT: Check pin 5 of 8J, and pin 10 of 8F too
 
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6k...1 and 12 both hi and pulsing

6j...same as above..hi..and pulsing but all four pins pulsing is at different tones...seems the pulse got higher on 4 and 7

8j..pin 5...low with a fast pulse..the pulsing is clear but fast

8f pin 10 is low with an even faster pulse than pin 5 of 8j

Above is same with attract and coined up
 
6k...1 and 12 both hi and pulsing

6j...same as above..hi..and pulsing but all four pins pulsing is at different tones...seems the pulse got higher on 4 and 7

8j..pin 5...low with a fast pulse..the pulsing is clear but fast

8f pin 10 is low with an even faster pulse than pin 5 of 8j

Above is same with attract and coined up

We may be beyond what a logic probe can test with. You might need to send it to someone like Gamefixer...
 
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