My megasquirt is doing some funny things and I was just wondering if some of you guys have any ideas to help me.

1. The first time I powered it up a little smoke came out by the db37 pins and hasn't happened since.
2. Pins 8 and 10 are a little charred. (Pin 8 is grounded straight to the battery, is this no good?)
3. Before upgrading firmware to 029w the injectors would fire and all three LEDS would flash if the key was turned forward. (engine off)
4. Before upgrading firmware my computer could connect to the MS after quite a few tries. I am not using a USB to serial converter.
5. After downloading 029w to the MS I have never established communication with the computer.
6. The LEDS no longer flash with 029w loaded, but the injectors still click.

The only good thing I've seen is that before I downloaded 029w I hooked up the CAS and could see RPM in megatune when I hand spun it. I appreciate any help. Thanks.

-Andrew

 

Andrew,

Any smoke is a BAD sign. Pull the unit out, and run through checks of the various circuits as detailed in the assembly manual. Replace failed components, and check your harness wiring well before trying again.

 

Alright, will do that. Do you (or anybody else) have any idea why I would lose connection after downloading the firmware? Or does nothing really matter until I figure what fried? Thanks for the help.

-Andrew

 

I had an odd problem with connectivity (but no smoke involved) as well. I could connect to it fine (usb adapter and all) one day, and the next it wouldnt work. I reloaded the 029w code (since the loading program and easytherm could still connect) and it magically started working again.

 

I think my problem is in the wiring, the unit worked very well with the stim, and had no communication issues. Do the issues above sound like bad grounding? I painted the engine bay so a lot of things aren't reconnected yet, I thought enough were but maybe I'm wrong. Thanks for any help.

-Andrew

 

smoke seems real bad as renns said ... I would re-double check your harness ... and yes going straight to the battery might cause noise ...

 

Thanks for the info on noise, I'm not sure what caused the smoke, but it only happened the first time, and no wires in the harness are touching. Since the unit works perfectly with the stim, and there has been no more smoke I'm guessing my problem is somewhere else. Thanks for the help.

-Andrew

 

The only problem with conectivity when I first built my MS was the firmwhere that was already on the chip had to be updated, updating went well but my megatune version was wrong, basicly it wasn't setup for the extra stuff. So it kept giving me errors and wouldn't let me start megatune till I fixed everything and moved some files.

 

I have no problem connecting when I power it with the stim, and no wires are touching in the harness so I'm thinking its bad grounding. Thanks for all the help.

-Andrew

 

Alright I've narrowed down the grounding problem. I have pin 9 grounded to harness wire 2R and pin 10 grounded to harness wire 3A. According to my wiring diagram these two wires are supposed to join before reaching the ground. Right now 3A is grounded, but 2R is not. Is it necessary to ground it to the harness ground, or can I just run a ground from the firewall to take 2R's place? I hope that wasn't too confusing. Thanks.

-Andrew

 

Problem solved, I'm a dumbass. Thanks for the help.

-Andrew