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Power Back Feeding


Jeffersonc
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Wiring my first ECU into a racecar I recently bought. Custom chassis and engine harness. I am getting electricity back feeding out from the +14 pin on the ECU. It starts once I turn on the main power safety switch to the vehicle. The engine is an RB25 in a 240sx chassis. The only way I can get it to stop back feeding is by unplugging the VCT plug at the solenoid. I have tried another solenoid for testing purposes but it continues to back feed. If I unplug the solenoid and install a light bulb, the back feeding stops. 
The VCT, CAS and Injector harness +12 power wires are grouped together and supplied from a fuse circuit from the custom fuse box. The coil harness +12 power is on a separate circuit as I was told to wire it this way.  
Any ideas where to start? The VCT is wired into AUX Output 2. 

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Fixed! the power circuit for the VCT, CAS and INJ was actually on a constant power supply. Well, a power supply that is hot when the vehicle safety switch is turned on. (it was considered the "dome light" circuit according to the fuse block manual I found) 
For a test I used an IGN switched power source and it's fixed.

Now question. Should the +14 power supply for the ECU have a fuse? It's currently a direct feed right off the IGN switch on the dash. 

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22 minutes ago, Jeffersonc said:

Now question. Should the +14 power supply for the ECU have a fuse? Its currently a direct feed right off the IGN switch on the dash. 

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Yes, ideally it would be fused at about 5A.

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