WARNING: This page is about a different car, the 1996 Acura NSX-T, 1996 Acura NSX, 1995 Acura NSX-T, and 1995 Acura NSX. However, it is still accessible from the selected car via links, so may be relevant.
This signals the ECM when the alternator (ALT) is charging. For troubleshooting of the FR signal circuit, see Fig 1
and Fig 2
.
Fig 1: Alternator (ALT) FR Signal Diagnostic Flow Chart (1 Of 2)
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 2: Alternator (ALT) FR Signal Diagnostic Flow Chart (2 Of 2)