possible ECM relocation

[corax]

I took off the dash today for some cosmetic repairs and noticed that there's a bunch of room behind there. So I pulled the ECM out from behind the passenger side kick panel to see how much room. 4crawler has already proven that the ECM can be relocated to the glove box to raise it up a bit higher, and that would probably be fine for 99.9% of the situations most of us would run into. The only problem is that I don't really want to give up the space in the glove box + I don't like the idea of the wires in my aging harness flexing back and forth every time I open the glove box (bend a paperclip back and forth a few times and see what happens).


Looks like it'd fit (might even be able to get the middle dash mount nut above the ECM back on):


So I set the dash pad back on and stuck the camera in the hole where the far right vent used to be.
Here's the clearance to the dash pad:

Firewall side clearance:


It'd be a little bit of work. Making brackets would be the easy part since there are holes at all 4 corners of the ECM to mount a sheet metal bracket to. The side towards the rear of the vehicle would be cake, the firewall side might need a little bit of creativity to mount to something solid and keep the ECM from bouncing.

The hardest part would be making the harness long enough to reach it, but I have an idea on that also. So next time I make a junkyard run I'm going to see if I can snag a new set of male ECM connectors and snip the female half of the ECM connector off of the board. From there I hope to epoxy the male terminals (in the female connector) into place so they don't move and just run wire between the two for a plug-and-play harness extension. You might be able to see in the pic below why I'll need to epoxy the terminals in place - the terminals don't move because they're all soldered directly to the board, there's no much in the plastic connector to hold them in place.


*NOTE* this ECM is for a 7MGE engine, but the 22RE ECM is the same size

Anyway, this is a project for further down the road and I'll need to gather some parts first, but I wanted to get everyone thinking about it a bit and see if there are any downsides . . .

[hunter4runner]

why not just cut a new hole in the firewall for the harness to come through? no extension needed.

[corax]

Originally Posted by hunter4runner

why not just cut a new hole in the firewall for the harness to come through? no extension needed.

That's a really good idea, and in my case might just work since the harness crosses over from the driver side - I'll have to check on that tomorrow, if it's gonna be that simple I'll probably get it done before putting the dash back in.

[Yotaoffroad27]

nvm I didnt read your whole post

[TheAussie1]

BUMP, I like that idea

[bigarms23]

id go glove box that way you have easy access to it

[corax]

Originally Posted by bigarms23

id go glove box that way you have easy access to it

that was the first time I ever pulled the dash off this truck and it only took 15 minutes. How often do you need to get to the ECM?

[hunter4runner]

Once every 30 years when the ecm frys
Even though the FSM always default to the ECM if you can track down a problem rarely have I seen one fail, due to time. Now water I've seen a ton fail due to water

[corax]

Originally Posted by hunter4runner

Now water I've seen a ton fail due to water

Yep, my windshield leaked onto this one and gave me a no start last year.
Luckily I diag'd it quick enough and saw the water drops on it. I took it apart, flushed it out with rubbing alcohol and dried it with my wife's hair drier - been working great since

[mattsonmj]

Originally Posted by corax

Yep, my windshield leaked onto this one and gave me a no start last year.
Luckily I diag'd it quick enough and saw the water drops on it. I took it apart, flushed it out with rubbing alcohol and dried it with my wife's hair drier - been working great since

While you've got everything disassembled might be a good time to think up some waterproofing ideas. Does the ECM need air for cooling or could it be put in some type of sealed box? Maybe skip that and just put some type of electronics friendly RTV sealant on the seams of the ECM itself.

[4runnerchevy]

Originally Posted by corax

How often do you need to get to the ECM?

I personally, like my A&W root beer float next to my ECU, next to the glove box cup holder. I like my glove box full of wiring and sensitive equipment, but thats just me. Never know when I'll swap some other motor in my runner, its kinda nice having access to the ECU.

Great idea ! Keith.

[corax]

Originally Posted by mattsonmj

Maybe skip that and just put some type of electronics friendly RTV sealant on the seams of the ECM itself.

- After water got in from the windshield leak, I taped the seams and all of the extra mounting holes. The connectors face downwards, so I'm not too worried about water getting past them unless I go for a swim

[hunter4runner]

4crawler had his in a large ziplock, which saves it from splashed and light water, rtv or tape around the edge and dialectic grease on the inside and I don't see water being a huge issue