the relay that is circled gets too hot to touch when ignition is on(even if car is not running).


Could anyone tell me anything about it?i know essentially nothing of the hardware of megasquirt... only software and tuning.


I apologize for such little information; i'm sure i can find anything out if more information is needed, just post.


thanks in advance.

Something's seriously wrong if the relay is getting hot. Check the relay board for bad solder joints and/or replace that particular relay.

thanks for the reply. do you have any idea what could be wrong? could this be causing my crank no start issue?

Originally posted by bnisson
do you have any idea what could be wrong?

Yes, like I said, there's either a bad solder joint or the relay is bad.

Originally posted by bnisson
could this be causing my crank no start issue?

Yes.

If it were my car, I'd ditch the relay board altogether and use the stock relays and fuses.

if i knew how to just ditch it, i certainly would.


could you help me find a link or something that will lead me in the right direction?


thanks for the help

Originally posted by bnisson
if i knew how to just ditch it, i certainly would. could you help me find a link or something that will lead me in the right direction? thanks for the help

You haven't provided any details about your MegaSquirt ECU; I have no idea what's in it.

It sounds like you're in a little over your head. You might consider taking your project to a professional and have them complete it.

its megasquirt v2.2 and i bought the car with it already wired in. i have done alot of research and i dont see how removing the relay/power board would help.


sorry if i am making this difficult.

Originally posted by bnisson
its megasquirt v2.2 and i bought the car with it already wired in. i have done alot of research and i dont see how removing the relay/power board would help. sorry if i am making this difficult.

If the relay board is causing your problems, removing it will help. It's generally not needed, and it just adds another layer of unecessary complexity.

If you want to keep it, then you're going to have to listen to my suggestions. Take the circuit board out of the enclosure and inspect the board for cold solder joints, cracked solder joints and shorts. If you can't find any faults, remove the relay that's getting hot and replace it.

If you don't know how to do any of this, you really need to let a professional handle this aspect of your project.

im sorry i didnt mention earlier, but i have done that. All the solder joints look fine and i dont see any shorts.


Like i said i would love to just take the relay board out of the equation, but i dont know how. Im sure i physically could, but i have no idea what to take off, what to re-route, etc.

I also forgot to mention I put in a new relay and it is getting hot as well.

any idea why?

Well, something's definitely wired incorrectly. I'd take a look at the FSM and the wiring diagram supplied by whoever built the MegaSquirt ECU. Those two documents should also provide enough information for you to remove the relay board. I don't know if this wiring diagram will apply to you, but here's the FSM and one possible wiring diagram:

http://www.symtechlabs.com/downloads/dl.php
http://www.symtechlabs.com/support/docs/MSWiringGuide.pdf

thank you very much for your help. i'll post on here if i need any more assistance

Originally posted by VelocitaPaola
Well, something's definitely wired incorrectly. I'd take a look at the FSM and the wiring diagram supplied by whoever built the MegaSquirt ECU. Those two documents should also provide enough information for you to remove the relay board. I don't know if this wiring diagram will apply to you, but here's the FSM and one possible wiring diagram: http://www.symtechlabs.com/downloads/dl.php http://www.symtechlabs.com/support/docs/MSWiringGuide.pdf

As you can see, i have all the wires into the relay board and the relay board connnected to the megasquirt board with a 37 pin harness. do i just unscrew the wires from the relay board and, idk, solder them to the megasquirt 37 pin male connector?

You will need to buy or make a new MegaSquirt harness. If you have a DB37 connector, shell and automotive grade wire, it's not too difficult to make your own. Otherwise, you can buy one for a reasonable price:

http://www.symtechlabs.com/catalog/premium-megasquirt-harness-p-37.html

ive been reading all day, and i think im on to something. I read how to wire up MS, and in the process read about the "flux residue"...

Pulled out the megasquirt board and it was pretty filthy. I just cleaned it and still no spark.

I think im going to try to figure out what is making that relay hot rather than take out the relay board. what do you think?

Sure, you could definitely do that. You'll need to start looking at everything that's connected to that relay. As far as I can tell, that includes the fuel pump, anything connected to the FIDLE line, the fuel injectors and the MegaSquirt ECU itself. You'll also want to check J1 and make sure it's configured right for whatever device is connected to the FIDLE relay.

so this is the bottom of that relay:





The two spots next to the solder joints look burnt. what do you think this could be? im thinkin about trashing the relay board now if they are beyond repair... hahaha

Originally posted by bnisson
so this is the bottom of that relay: The two spots next to the solder joints look burnt. what do you think this could be? im thinkin about trashing the relay board now if they are beyond repair... hahaha

bump... still stuck

The board looks fine to me. I'd start tracing all of your wiring to look for shorts or damaged components.

Originally posted by VelocitaPaola
The board looks fine to me. I'd start tracing all of your wiring to look for shorts or damaged components.

even considering those places on the bottom of the board?

Originally posted by bnisson
even considering those places on the bottom of the board?

Yes, of course. You didn't take the clearest pictures, but those marks don't appear to be over any traces.