TS2JZ Plug-in not getting power to main relay

[kdaig1]

Hello I have a TS2jz v1.2 ECU with a factory 2JZ-GE harness 

 

Initially I didn’t realise it had a JZX100 map loaded and when I connected the ECU, it powered up and the fuel pump ran, and continued to run until I pulled the EFI main relay. 
 

I then benched the ECU, loaded 2JZ base map from the default files. 
 

I am now not getting power to the EFI main relay at all. I have:

checked the relay and fuses, verified there is constant power to ECU pin 33, verified there is switched power to pin 1, there is no power from MREL pin 24 to the EFI main relay. 
 

looking at the diagram it doesn’t look like there is anything else required for mrel to activate the relay? 
 

if I jump pin 3&5 of the efi main relay, the fuel pump turns and the ECU powers up. The issue appears to be with MRel output pin 24.

any ideas on what to do next? Cheers 

 

 

[Vaughan]

36 minutes ago, kdaig1 said:

verified there is switched power to pin 1, there is no power from MREL pin 24 to the EFI main relay. 

There is a diode on the bottom board between pin 1 and pin 24, maybe open up your ecu and see if you can spot any fried components.

[kdaig1]

The circled component appears fried. Is this what you were referring to? 
 

Noting I am not an electronics tech, what is the best course of action if this would explain the symptoms?

 

cheers. 
 

side note: considering I am not running any evap or vsv would there be any harm in bypassing mrel and activating 24 from switched ignition power? 

[Adamw]

On 11/24/2023 at 3:12 PM, kdaig1 said:

side note: considering I am not running any evap or vsv would there be any harm in bypassing mrel and activating 24 from switched ignition power? 

The ECU hold power function then wouldnt work for keeping the ecu alive after ign off to reset the stepper motor.  

Contact [email protected], it will likely be a warranty repair if the diode has failed.