Chrysler Repair: 98 Cirrus: Power Door Locks

Question
1998 Cirrus LXI, 6 cyl, automatic -- New to me.

Having problems trying to solve an issue with the power door locks.
The following switches and keyless entry ONLY Locks/ Unlocks the Right Rear Passenger Door:
Driver Lock Switch
Passenger Power Lock Switch
Keyless Entry Remotes (I have 2 that do the same thing)

It does sound like the actuators are working.

I do not think it is a fuse, because the other things that goes to the fuse controlling the power locks all fine.

I've sprayed a little WD-40 on the driver's power lock switch. After doing this it is still just locking and unlocking the passenger right rear door only.

I have the original Window Sticker and Owners Manual for this car. On the window sticker, under the Interior Features, it has "Locks - Power Auto Speed Sensitive". According to the Owners Manual this was "optional". I'm assuming that since it is listed on the window sticker that this car is equipped with this option. This is suppose to automatically lock the doors when vehicle speed is above 15 mph.
According to the manual, this can be turned off or on, using the door lock switch.
I am unsure whether this option is off or on. With all the doors unlocked and driving the car, none of doors lock and I do not hear any of the actuators trying to cycle.

All the locks will operate manually.

Answer
Hi Linda,
The power door locks are controlled by the body control module which is under the dash at the left hand end, located on the back side of the fuse box, which is hidden behind the left end cap of the dash. The fact that one of the locks works and the others make noises suggests that the wiring is still connected properly but for some reason the locks are not actually doing their job. Each lock is operated by 2 separate wires coming out of different pins on the body module plug no. 5, with no common wires.
I wonder if the voltage level of the overall circuit might be low due to some corrosion around one of the fuse sockets that power this overall circuit. It is not clear which of the fuses for the module power the door locks, so you would want to remove and check fuses 4, 5,8,9,11, and 15 in the fuse box behind the end cap and be sure they all look shiny as to their contacts. Other than that you could check the body control module plug (one of 5 such plugs on the module) which is black and has 20 pins. It is possible that water has dripped down on the plug from the windshield and disturbed the pin/socket contacts. Try spraying from electronic circuit cleaner on the plug and its socket. That plug is mainly carrying the door lock power wires but also the fuel level sensor and the door ajar sensors so notice if any of those are also impacted.
I don't see any other explanation for the situation unless the door lock motors are wearing out individually from usage.
Roland