No Comm

[TypeSL2]

Hi, my name is James and I am very new to the MS. I purchased this particular setup used about 2 years ago. Am just getting around to installing it in my car. I can't get it to communicate with hyperterm or megatune. Not sure what which code version is in it, but it is the MSI v2.2. I have done most of the tests in the communication section, and have found that I have 6.23v on what I believe is the wrong terminal of the max232 chip. I am not sure how the chip is numbered, but I am showing voltage on what I have concluded is terminal 13. Could this be causing the problems I am having? Thanks for any help, and I apologize if this question is very newbish.

Oh, and I found this thread while searching, viewtopic.php?f=30&t=31197&p=197859&hilit=max232#p197859, and this is also what leads me to believe I am having trouble from the max232 chip.

James

[huafist]

If you look at the chip, the edge with the indentation is where 1 and 16 are. If you look at it so the indentation is pointing left (serial connection pointing left), 1 will be on the bottom, and 16 on the top. You shouldn't see over 5vdc at that chip,and that should only be on pins 16 and 2. I can't offer any more help without plugging one up in the garage and probing it myself, sorry.

[TypeSL2]

Well, that confirms it then. I have 6v on terminal 13. Terminal 13 isn't even listed in the manual as to what I should be seeing there, so maybe that terminal isn't used? Either way, I don't have any voltage at pin 16, but I know that there is voltage going into the board. With the ms hooked up to my car, I tested for voltage on the bottom of the board where the db-37 pins are soldered, and I am seeing b+ voltage on the bottom.

James

[Matt Cramer]

Have you tried a port check? If so, what was the result?

To do this check, you'll need the program portcheck.exe, which comes with most MegaTune versions, including the one on the DIYAutoTune.com website. You'll find it in the MegaTune2.25 folder. If you don't have a copy, download it here:

http://www.DIYAutoTune.com/downloads/tu ... tCheck.zip

Power up the Megasquirt and connect it to your PC. You do not need to open the case and should not put the boot jumper in place for this test. Close MegaTune if it's running, and run the portcheck.exe program. When this program starts, it will scan the available COM ports.

If the port it's scanning is not connected to a working Megasquirt, or it's on the wrong speed, it'll say "No connection made." If it's on the right port and right speed, it will give you the version of the Megasquirt firmware that's on the Megasquirt. Note that some Megasquirt firmware versions will look like earlier versions with this test - for example, 029V identifies it as 029Q. This is for backwards compatibility.

If you get a port where it replies with "S" or something else that doesn't look like a firmware version, this port is probably a fake COM port that echos back everything that's typed.

[TypeSL2]

I performed the port check as advised, but it came back COM5 no connection made. I tried with different buffer settings and nothing changed it. I have the port set for 9600 for the MSI, and that is the same rate that I use when trying to connect to hyperterminal, but I get nothing during the echo test or port check. So I still don't know what firmware version I have. Any other suggestions?

James

[TypeSL2]

So, I have decided to start from the very beginning of the manual and check everything. Orientation, size, condition of solder, all of it. I have come across something that I have searched and was unable to determine why it was done.



In the Power supply circuit, one lead on C17 has been cut and jumpered to L1. I don't know why. I am running a flyback board, and the previous owner had started to wire in stuff for the ignition control. So I looked in the manual for any mention of why this jumper could be added, but have come up empty handed. Any ideas?

Oh, and I found this because I really was just going to check power distribution because I don't have any voltage at the processor when the board is plugged into the car, even though I do have 11.60v at the DB37 connector. This was checked on the bottom of the board.

James

[Matt Cramer]

This may have been done to bypass a burned trace, as normally C17 gets its power from the top leg of L1.

[TypeSL2]

Well, I will take a look at the board when I get home tonight.

James

[TypeSL2]

Pics:

Problem area I was talking about


I think they missed a hole...


Extended view of problem area


Random Shot


Questionable area on the bottom side of the board, near the map sensor


Another shot of the bottom side






Thoughts?

James

[Matt Cramer]

Looks like the 12 volt power feed got burned.

[TypeSL2]

Where is that located? Is it something that I can replace/repair and still use this board?

James

[Matt Cramer]

Where is that located?

It's in the burned part of the picture near the MAP sensor.

Is it something that I can replace/repair and still use this board?

James

Probably, depends on your soldering and troubleshooting skills.

[TypeSL2]

I know this is really getting annoying, but I am really stumped as to what could have caused this, and what I can do to fix it. I tested with an ohm meter to see if this section still has a good path.



It seemed to be fine as it only showed .01-.03ohm resistance from up near the map sensor to the open socket, and same for the section from the map sensor down to the 2 soldered terminals at the bottom of the pic. The copper ribbon looking section is peeling away from the board, but doesn't really show to be bad.

James

[Matt Cramer]

It appears to have been an excessive current draw or voltage spike.