Why my speedometer work while I am driving 1992 Cadillac Brougham?

Your 1992 Cadillac Brougham's speedometer works because it's connected to the vehicle's drivetrain. Specifically, it receives its signal from a vehicle speed sensor (VSS). This sensor is usually located on the transmission (or sometimes on the differential) and measures the rotation of a drive shaft. This rotational speed is translated into a signal that's sent to the speedometer, which then displays the vehicle's speed.

If your speedometer isn't working, the problem lies somewhere in this chain:

* Faulty VSS: The most common culprit. It might be worn out, damaged, or have a bad connection.

* Wiring Problems: A broken wire or a poor connection between the VSS and the speedometer could interrupt the signal.

* Faulty Speedometer: The speedometer itself could be malfunctioning, though this is less common than a VSS issue.

* Transmission Issues (rare): In some cases, problems within the transmission itself can affect the VSS's ability to accurately read speed.

* Instrument Cluster Problems: The instrument panel containing the speedometer could have a failing component or internal wiring issue

If your speedometer *is* working, then there's no problem to fix! The question is a little unclear; perhaps you meant to ask *why your speedometer isn't working*?