S2000 red light blinks- enhanced board

[puckhead]

red light on mpu blinks on boot , its an enhanced board .dont have another game or board for testing. every once in a blue moon it was booting  normally, but hasnt in the last 30-40 tries .  zero corrosion, battery was a 3.6 volts.  new coin battery. with clear chip, top amber just blinks forever.  removed varta and u16, no change.  ballasts disconnected, no change. swapped power supply with my other game, no change.  checked pins and used de-oxit on backboard connectors.
any ideas??

thanks

[Shaggy]

You say it's a new coin battery. Have you made sure the solder connections are good there? And the polarity?

Dave

[puckhead]

good and good

[qbert]

Was the red light blinking (boot problems) before you removed the Varta?It is not sounding good for the MPU.
 Have you tried reseating and checking pins on all of the removable chips on the MPU/legacy board?

Rich

[puckhead]

happened before and after battery removal.  i did reseat all socketed chips and checked pins

[puckhead]

i bought a new mpu , replaced coin battery. charged varta battery for a day, held a good charge, and it booted right up. booted it like 50 times. 51 st  time, back to the same crap, red light blinking.  ballasts are unplugged, different power supply. to me, if its not the motherboard, is there anything else i could look for?

thanks

[Ken]

I am color blind so .. amber .. green .. I can't tell you which one is which but I know the red one is the bottom one.

If you put the 224 in and the 4 top lights come on .. then put the 45 in .. if the top two lights come on and the third light down blinks then try a power supply.

[qbert]

What is the voltage of the Varta now. If you just booted and did not leave the machine on for any period of time it may have discharged especially if it is not new. You can charge an old battery for a month and it still is an old battery.

[rickhunter]

The flashing red lights have happened to me a couple of times on enhanced board, always the Varta Battery.  I have since done the mod to remove the battery and no more issues.

[puckhead]

varta right now is 3.9 volts.    i did the u16 mod on the old board, didnt help. i dont want to mod another board if its not the problem. i might solder on a new varta just to see.

[qbert]

Wasn't the first board bad before you did the Varta removal mod? How are you charging the Varta on the board? Are you using some external charger?

[puckhead]

the first board sort of did the same thing.  it booted a few times, then nothing bu red blinking from then on.  i charged the varta on both boards by leaving the machine on for 24 hrs.  i removed the varta and u16 on the orig board, and it still wouldnt boot. both boards have new coin batteries.

[qbert]

Once in a while the pins going to the backplane board are bent or just not making good contact. Make sure you put the MPU in firmly.

[cowboygames]

When you got the new board, did you have to transfer the ram chips from the old board? Or did it come with them?

[puckhead]

came with