As far as I can determine, only the Canadian models have a DRL system. There isn't much info on it in US repair manuals. I own a 1994 Canadian Villager. On my vehicle, the module is screwed onto the passenger side strut tower, right behind the cruise control servo. Not sure if the 1998 models are the same, but should be pretty similar.
Inside the engine compartment by the passenger strut tower
where dose daytime running lamp module go on92 mercury grand marquis need to replace one
where is the running light sensor on a 2003 grand marque
The cruise control module of a 1993 Mercury Villager is located under the passenger side of the dashboard.
A ( Daytime Running Light ) module
The daytime running light module on a 2005 F-350 is located underneath the hood. The module will be in the relay box.
The cruise control computer module is located on the passenger's side of the engine compartment on a 1993 Mercury Villager.
Powertrain Control Module
It may not have daytime running lights.
Inside the distributor
don't believe they had daytime running lights in 1991 topaz
Check your owners manual for the location of your daytime running light module. The manual should have a diagram with its exact location.