While less likely, other possibilities include:
* Bad ground connection: A poor electrical ground connection in the tail light circuit can cause intermittent problems, including rapid flashing.
* Faulty wiring: A short or break in the wiring leading to the tail lights could also cause this.
* Faulty tail light assembly: Although less common, there might be an internal issue within the tail light assembly itself, even if the bulbs appear okay.
* Faulty flasher relay (unlikely): While the flasher relay is usually associated with turn signals, a malfunction could, in rare cases, affect tail lights, but this is less probable given the symptom.
* Body control module (BCM) issue (least likely): A problem with the BCM is possible but usually presents with other electrical issues.
The most likely culprit is a blown bulb. Check all the bulbs in the affected tail light assembly (brake, turn signal, running light) and replace any that are burnt out. If the rapid flashing stops, you've solved the problem. If not, then you need to investigate the other possibilities, which may require a qualified mechanic.
