Help needed on 99 Pathfinder battery drain and SECU

[DonovanB]

I am trying to isolate the source of a serious (800mA) current drain when parked on my '99 Pathfinder SE. Battery is new. Alternator is good, but battery is dead after parking overnight. I have isolated the circuit responsible to fuse 24 (ELEC B), which powers a number of things, including windows, door locks, keyless entry, power antenna, and dome lights. I suspected the power lock switch or actuator on the passenger side because it is intermittently non-functional. But disconnecting all harnesses to the right side front door had no effect. I still measure 800mA across fuse 24 with everything shut down. I also eliminated the power antenna as the culprit. When I pull the plug on the wiring harness into the smart entry control unit, the current drops to an acceptabl 60mA, so it something down that path.

Does anybody have experience with similar SECU problems? I could replace the unit or start troubleshooting all the open-door switches and the other three power locks, which are all controlled by the SECU. I've solved my dead battery problem, but with the SECU unplugged I lose the power locks. I've never had a key fob for this vehicle, so I didn't have KE to start with.

Thanks for any suggestions.

[Towncivilian]

If you haven't yet, you can find a schematic of the SECU on page EL-277 of the factory service manual and you can search what use fuse 24 by searching for "no. 24" - there are 22 items. I wonder if it may be a relay that's stuck on?