Smoke from ECU

[dark_uk]

Hi all,

After replacing the clutch I made an whoopsie and connected the engine earth to the starter live. On first start we noticed the temp gauge go to max and then smoke from the boot. The car has since been wired correct and starts and runs however.

The alt isn't charging and there is no speedo or reverse light.

A component looks to have burnt out, it comes out of the loom right before the ECU and is a red and silver dotted wire. I can add images yet as not made enough posts.

Does anyone know what this could be?

[outrun]

The speedo, alt and tps are all connected and terminate at one of the white plugs in the engine bay fuse box.

Test the black and yellow (iirc) wire between them for continuity. As that is a common failure point.
Usually caused through age/wear and tear, not a smoking ecu from sending 12v through your grounds, mind!

[Nic]

A component looks to have burnt out, it comes out of the loom right before the ECU and is a red and silver dotted wire. I can add images yet as not made enough posts.

Does anyone know what this could be?

It'd help to know what MR2 model it is.

Do you mean there is something spliced into the wiring loom? If so it's most likely either a km-mph speedo converter (if Japanese) or fuel cut defended (if turbo).