The problem could be the ECU, but more likely, the wire from the
fuse to the ECU connector is shorted to ground under certain
conditions. Replace the fuse and without driving the car, locate and
wiggle the wiring harnesses between fusebox and ECU. You can also
unplug the ECU connector and ohm test the wire from the fuse to the
correct ECU pin in the connector, and from the fuse to ground. If there
is continuity to ground, you have a short somewhere.
—Jim O'Neill
Chino Autotech Inc.