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RB20 ECU power info needed

Hey all,

Went to test my ECU was working for my RB20 into S15 swap today and was unable to get consult working.

RX,TX,CLK all have continuity and are correctly pinned in the consult plug. Consult also has 12v and earth.

A little probing revelaed that the ECCS relay is not triggering, i have 12v on both sides of the coil with the ignition off (which is correct as per the nissan r32 servcice manual). I believe the ECU is supposed to switch and earth on pin 16 (ECCS Relay) when it turns on. So lets check if the ECU is turning on.

Pins 50 and 60 (ECU earth) both have a good earth.
Pins 49 and 59 (ECU pwr supply) both have 12v with ignition on
Pin 58 (Battery pwr supply) has 12v battery constant
Pin 45 (Ignition switch) has 12v when ignition is switched on

If all my power and earths are good then the ECU should be turning on? But yet i can't connect via consult and it's not triggering an earth on pin 16 (ECCS Relay) and triggering the relay itself. As my ECU has a NIStune and NIStune flex fuel board fitted so the little LED's have been removed, so unable to tell that way.

Will be checking it all again tomorrow but just after any ideas on why it seems the ECU is not turning itself on.

Thanks
 

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Got a spare ECU? Sounds like everything is working ok so perhaps an ECU fault. Checking against a known working ECU is a quick and easy way to rule this out

Seen as the ignition key should be the trigger for the relay (to earth the ECCS coil side), it should activate it

Also check your fuses. I know my R33 has 2 engine control fuses and one of them (if installed) makes the car stay on even with the key out so maybe something silly like this?

Switched with a known working ECU and still a no go. Did some more investiagatin (using R33 manuals which were a little more clear) and it had pretty much the same troubleshooting info. It did say to check the ignition system (pins 10 and 20) and the injector (pin 107,108 and 116) earth points. The injectors i figured i didn't need those pins earthed as the actual injector signal pins pull to earth to activate the injector. And the ignition system i wasn't going to earth through the ECU as i am using yaris coils and was going to delete the ignitor.

Turns out that they all need to be earthed for the ECU to be fully working. As soon as i connected 10,20,107,108 and 116 it turned on fine and fuel sprayed everywhere in the engine bay as i have the fuel line disconnected and the pump started priming haha.

So for future reference, don't just disregard the nissan manuals (even if they don't make complete sense sometimes)

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