Not 100% sure on your model but here goes. There are 2 relays that are part if RAP system, the rap relay under the sill and high power relay under the hood in relay center. Very often it is the sill relay that has corroded , been 2 or 3 around here last few months with problems with that relay.
If the relay is good it could be a grounding issue as they use grounds to energize the relays not the hot. Your year should be similar to late 90s...
By "sill" do you mean the wiring harness "chase" or enclosure that runs from the trunk under the driver's door to the dash? I did find a relay in there but it wasn't for the RAP. Under the hood in the fuse compartment, under the plastic shroud there are 6 relays, none marked as Accessory or RAP on the diagram in the cover. Is there another wiring "chase" under the passenger door?
Yes the chase where you found relay. It is one of two that are part of RAP. The other i believe is called inadvert power relay and will be separate from the main relay center. If one fails the second acts as backup basically and when it fails closed it never shuts power off. The BCM also may be an issue if the relays aren't bad. Did you pull the codes to see what comes up? These cars are very picky about grounds as they use them to turn stuff on and off.