• We do NOT believe in a fuse or breaker between the ECU and it's power source, however, we do recommend a temporary in-line fuse of 5A until all initial installation / run-ups have been completed.  Be SURE to clearly mark this to be removed since the fuse WILL fail at takeoff power.  
  • Never engage the starter by touching the starter wire to the positive battery terminal or to the positive battery BUS.  It will cause a large spark and possible reverse current, damaging the ECU.  Always complete the starter relay wiring before starting.  
  • Make sure batteries are fully charged prior to the first start and if using lithium batteries with a built in battery management system, add a lead acid battery in parallelly during the first starting attempts to be sure the alternator has a load.  This further protects the ECU.  

We sometimes have customers calling asking why their engines don't start.  After a return of the ECU, we find that it has either not been wired correctly or reverse polarity has destroyed a diode.  If your wire loom has 2 separate wires for the ECU, step one is to combine them as shown here: