Hi guys, i have a msII v3 and i gave it to some one from the electrical team of the fsae car we are building and he did a crap job so i got it back and went over everything and reheated all the components again since he had cold joints and all. i cleaned all the flux with alcohol, checked the db9 cable, checked all the components in case of a bridge, checked all diodes and capacitors and checked the processor with another ms and it worked so that's out too. Checked U6 and the voltage regulator and everything is in spec, but i still cant upload any firmware with this ms, it says unknown error status e=0x00. i connected the processor to another ms and i was able to upload a firmware on that one but not on the one i am trouble shooting. Any other ideas of what i should check? thanks in advance

 

I would double check the power circuit first (look for componts installed backwards etc) followed by the serial circuit components.

Ken

 

i pass all the test up to the one where you need to upload the firmware, but since the whole ms is build i am confused if another component after the upload of the firmware would cause this. Will do, ill double check that.

 

k so i rechecked the power circuit one by one and all the components were placed correctly, but before i had checked the 40 pin socket voltage with an led, so today i tested it with a multimeter and saw that i was only receiving 1.8 volts instead of 5v. I went back and checked the voltage regulator on my working ecu and on the left one 12v and 5 on the right one so its fine, but when i checked the non working one i only got 2.26 from either left or right pin. Does that mean my U5 is shot? Would low voltage not let the ms down loader communicate with the ms? Is this the correct replacements? http://search.digikey.com/us/en/prod...CC0T-ND/722252

 

Low voltage could also be caused by some other part of the power supply circuit not being installed correctly.

You want to install an lm2937 or lm2940 if you're replacing the voltage regulator.

Having low voltage would definitely keep the processor from powering up, and therefore keep firmware from loading.

Ken

 

K thank you. I will check each component and make sure they are working properly because installation wise they are correct. I checked all the markings and they all check out.

 

i have a friend that has worked ms before and he told me to check D9, that if its bad the voltage regulator would just put out the same voltage thats coming in. How could i check if the diodes are working properly?

 

Depending on what type they are they should block current in one direction. Some DMMs can also measure their voltage.

Ken

 

so following the diagrams i went straight testing from the raw 12 volts of the stim first and it gave me 12 volts, then the moment i connect it to the ms it dropped to 2 volts, even the MOV1 has 2 volts. Those this mean its a component on the power circuit or it could be any other component of the whole ms thats making this voltage drop happen? how could i trace the culprit of this? thanks

 

Sounds to me like there is a short circuit or similar, that's going to be tough for me to debug over the forum. You may want to send it off to have it fixed.

 

so to sum it up, it could be a short anywhere in the ms, not necessarily in the power circuit right? Since the whole thing is built, any short in the whole board could be draining it? Thanks alot for the help

 

I think so yeah. I would also think whatever component it is would be getting very hot.

Ken

 

maybe i can use a laser temp gauge and look at the temp for each component. thanks for the help