Where is the on-board computer located on a 1989 S10 pickup?

The 1989 GMC S10 (and Chevrolet S10) doesn't have a single, centralized "on-board computer" in the same way a modern car does. Instead, its electronic control functions are distributed among several modules. These modules are generally located under the dashboard, in the engine compartment (near the firewall or on the inner fender), and potentially in the rear of the vehicle depending on options.

There isn't one specific location to look for a "computer." You'll find various control modules such as:

* Powertrain Control Module (PCM): This is the most significant module, controlling engine functions. It's likely under the hood, possibly near the firewall or attached to the inner fender.

* Body Control Module (BCM): This manages various body functions, like lights, power locks, etc. This is typically under the dash.

* Other modules: Depending on options (like automatic transmission, air conditioning), there will be other modules for those systems. Their locations vary.

To find specific modules, you'll need a wiring diagram for your specific 1989 S10 model and trim level. A Haynes or Chilton repair manual would be invaluable for this. These manuals usually have diagrams showing the location of these modules.