JimStim problem

OldTimer2 · Post by **OldTimer2** » Thu Oct 04, 2007 1:50 pm

JimStim

The power voltage drops down to 5+ volts out of the supply and the 3.3 regulator gets very hot as well as theCPU. If I unplug the CPU all is good, infact I was able to plug the stim in and check the ms2 power supply and the voltages were all OK.

I have checked the Diode and the other components; they seem to be in correct.

Washed the board and checked for bridges

Could it be the processor is bad? I don’t think I zapped it for I have handled many computer chips and never damaged one.

The voltage and the resistance for the CPU socket pins would be good if that is available.

I checked the socket voltages , there are two 3.3 V and one or two 2.6V.

The resistanse on the pins dont look bad and there is 1 ground.

Any help would be appreciated

Paul

Post by **jsmcortina** » Thu Oct 04, 2007 2:04 pm

Does the 3.3v regulator get hot with the JimStim CPU unplugged ?

What current is the unit pulling from your power supply?

James

OldTimer2 · Post by **OldTimer2** » Thu Oct 04, 2007 3:07 pm

The 3.3v regulater dont get hot with the CPU out

I have not checked the power supply current but for it to drag it down from 17+V it would be near the 300mA max for the adaptor, would you no thank so!

Post by **jsmcortina** » Thu Oct 04, 2007 3:24 pm

Are you sure the CPU was installed the correct way around?

James

OldTimer2 · Post by **OldTimer2** » Thu Oct 04, 2007 3:59 pm

Yes- the notch to the out side of board and the CPU the same

racingmini_mtl · Post by **racingmini_mtl** » Thu Oct 04, 2007 4:27 pm

Is that possible that something shorted on the bottom of the board? Did you have the board on something conductive that could have shorted some components temporarily?

It really sounds like the CPU is fried because it basically fails as a short which would produce the symptoms you mentioned. And since there are 5V and 12V signals on the board, if anything conductive comes into contact with the bottom with all the solder and cutoff leads, there is a real possibility that one of these will reach the CPU and since it is rated at 3.3V, any 12V or 5V that reaches the CPU will fry it.

I assume you got the kit from DIYAutotune. You should talk to them to see what they say. If you need another CPU, I have some available.

Cheers,
Jean

OldTimer2 · Post by **OldTimer2** » Fri Oct 05, 2007 12:55 pm

I could not log in until now,wanted to say thanks for the help James and Jean.
Getting new CPU from DIYAutotune.

You can close this thread if you want to now.

Thanks again

Paul

Post by **jsmcortina** » Fri Oct 05, 2007 1:28 pm

Let us know your progress with the new CPU. Want to know the issue really is closed off.

James

OldTimer2 · Post by **OldTimer2** » Sat Oct 06, 2007 8:51 am

Will do.