DTC P1607: Powertrain Control Module (Pcm) Internal Circuit
WARNING: This page is about a different car, the 1998 Acura 2.3CL. However, it is still accessible from the selected car via links, so may be relevant.
FAILURE "A"
Perform PCM reset procedure. See PCM RESET PROCEDURE/CLEARING CODES under SELF-DIAGNOSTIC SYSTEM. Turn ignition on and wait 3 seconds. If DTC P1607 does not reset, problem is intermittent. System is okay at this time. If DTC P1607 resets, substitute a known-good PCM and recheck. If symptom or problem goes away, replace original PCM.