How do you locate the door sensor that controls overhead light in cab of a 1998 Ford Ranger?

There's no standard door sensor directly controlling the overhead cab light in a 1998 Ford Ranger. The light is usually controlled by a switch on the light fixture itself (often a simple push-on/push-off) or by a courtesy delay system that times how long the light stays on after the door is closed.

The system works like this:

* Door Switch: When you open the door, a door jamb switch (located in the door jamb itself) signals to the Body Control Module (BCM). The BCM is the central electrical brain for many vehicle functions.

* BCM (Body Control Module): The BCM then sends power to the overhead light circuit. This isn't a direct connection; the BCM acts as an intermediary.

* Overhead Light Switch/Timer: The light might have its own switch, overriding the BCM's signal. Or, the BCM might control a timer circuit that keeps the light on for a short period after the door is closed.

Therefore, you won't find a single "door sensor for the overhead light." Instead, you'll need to troubleshoot this way:

1. Check the light switch itself: Make sure the light switch in the overhead console isn't faulty. Try manually turning it on and off to see if it works independently.

2. Check the door jamb switches: Inspect the door jamb switches on both the driver's and passenger's sides. They are typically located within the door jamb area and are usually small plunger-type switches. Check for damage, loose connections, or if they are actuating properly when the door opens and closes. You'll need a multimeter to test if they are providing a signal when the door is open.

3. Inspect wiring: Visually examine the wiring harness leading from the door jamb switches and the overhead light. Look for any broken wires, loose connections, or corrosion.

4. Check the BCM: A faulty BCM is less likely but possible. Diagnosing BCM issues requires specialized tools and knowledge, often making it necessary to take the truck to a mechanic or a specialized auto electric shop.

5. Check the fuse: The light might have its own fuse; check your owner's manual for the fuse box diagram and check the appropriate fuse.

In short, the "sensor" isn't a dedicated part for just the light. It's a part of a system involving the door switches, the BCM, and potentially a timer circuit or the light's own switch. Focus your search on the door jamb switches and wiring, then move on to the BCM as a last resort.