MSefi.com read only forum (Jan.15,2018)

Firstly I have MS2 with V3.0 Board.

All things were going well. Had managed to link up to TunerStudio and transfer software. Next day no connection. I checked the DB9 pins 2 and 3 loop and got the correct response. But when I do the loop through Pins 12 and 13 in the Daughterboard socket - no response.

A little investigating found that Pin 2 on the DB9 is connected to Pin 14 (MAX232 - T1OUT) and Pin 3 on the DB9 is connected to Pin 11 (MAX232 - T1IN). But there is no connection between Pins 11 and 14.

I have now sucked out the solder on these two pins and retested - no change.

I have also scrubbed the base with IPA.

I did find that the jumper between JS10 and IGN had been pierced by one of the tails.

Are there any more checks I should do (ie other components) or am I missing something?.

Cheers

Steve

Yodapom wrote:A little investigating found that Pin 2 on the DB9 is connected to Pin 14 (MAX232 - T1OUT) and Pin 3 on the DB9 is connected to Pin 11 (MAX232 - T1IN). But there is no connection between Pins 11 and 14.

These pins should not be connected - the MAX232 is a buffer type device. I would check to make sure it's got good power and ground.

Matt,

Sorry for not getting back to the forum, I traced the initial fault to a crook Stim chip. Ive have now replaced it and I also found my D20 was backwards. Not sure why it worked well to start with. I removed the D20 with the intention to replace it and decided incorrectly to see if I actually have power at U5 and I did then it started to drop off....A very small puff of smoke later I think I burnt something else now. What was D20 protecting?? I had thought by removing it I would have been still able to test for power on the U5.

Help!!!!!!

D20 is part of the flyback voltage clamp circuit on injector channel 2.