So my story is I have 2003 SE. Started it yesterday. Smelled roasting electronics. Finished my trip started the car again. Went home. Read codes P0650. Now all indicators that would normally illuminate during startup stay on. Wipers work etc. ALL WITH NO KEY. Security light is solid. ECM is fried. I Have another ECM. I'd like to troubleshoot to see if this is a fluke failure or was caused by another issue.



Any help would be greatly appreciated.

 

since you're a 2003 we can rule out the iacv

auto trans? if so are you still running the original motor mounts?

 

^^^ +1 !
If your car is an AT, and the original engine mounts ("with wires") are still connected, then that's what your problem is ............ .

 

Yes AT yes all factory motor mounts. Can you just eliminate the wires?

 

What purpose do these mythical wires serve?

 

you can unplug the mounts and it will run fine, most people will replace with mounts with the MT version (the transmission mount isn't interchangable)

the two AT mounts on the crossmember are electronically controlled to soften the mount at idle/low speed to reduce vibration in the vehicle. they stiffen at speed so performance isn't effected

when the mounts go bad this is one of the known culprits to take out the ecm, unfortunately.

did you notice any buzzing or whirring from the engine bay when turning the car on/off prior to this happening?

 

It appears that you are not very well informed about the positives/negatives of this car. Read this: https://drive.google.com/file/d/0B6O...hibHlkRmc/view .... and good luck.

 

I have. Since right around when I replaced the alternator. That noise is the hydraulic pump I bet. Do I have 1 or two of these mounts. I think I've read just one up front. I've just done my reading. It does say newbie by my signature.

 

iirc 02-03 only have one electronic mount!

 

Thanks for all the help.

 

I've seen other members implementing inline fusing between these mounts and ECU. Does this seem practical?

 

sure it seems practical, it's a simple fuse (we all know what fuses do). probably a DIY job so if you're not confident in your ability best leave it alone.

can you link to where you read other members have implemented this fuse? i know maxiiboy has talked about it but i don't recall seeing where anyone has done it.

 

https://maxima.org/g/picture/5334005

 

looks pretty simple

 

But why bother with a fuse?

At this point said mounts are trash and should just be replaced with non electronic mounts I bet you couldn't tell the difference between a non working electronic and a solid mounts... BTW if anyone ever complained about cabin vibrations they're

 

I could be wrong, but I think that fried component is a film capacitor. The little round "can" shaped devices are electrolytic caps. If so, I would say it saw more voltage than it was rated to handle.

Anyway ... you might be able to replace that part and put this ecu back in service. Worth a try. Hopefully it got sacrificed and didn't kill any other components up or downstream. I guess it's the logic chips that you'd be most concerned about.

Just noticed the little blue component next to it is also fried. Still - might be a part you can replace also.

 

Yep, a little easy soldering is worth a shot. If you're lazy, you can just spend 30 bucks at the junkyard/ebay and buy a cable/NDS2 for 60 bucks.