How to test and fix a PGM-FI main relay - Honda/Acura

Honda PGM-FI Main Relay Testing (1998 Honda Prelude)
How to test and fix a main relay on a Honda or Acura.

Engine Performance Diagnostics chapter 18

Symptoms (typical of a main relay issue)
intermittent no start
start/stall
stalls and will not restart for a period of time

Fix
replaced PGM-Fi main relay fuse

Tests shown
how to determine what is powered by the main relay
main relay wiring diagram review
how to identify condition of the main relay by testing for power at the fuel injectors and idle speed control motor
how to test a PGM-FI main relay
how to locate the main relay
how to remove the main relay
how to locate a cracked solder joint on a circuit board

Tools used
incandescent test light
soldering gun

Playlist
(Chapters 17, 18 and 19) Fuel Injector Testing
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