Which statement would cause cab signals to be considered inoperative en route?

Which statement would cause cab signals to be considered inoperative en route?

• A. The engine is not equipped for cab signaling
• B. The cab signal system is functioning properly
• C. The departure test has been completed within the last 24 hours
• D. The engine has not received a departure test while en route

Answer: (D)

Cab signals must be verified by a departure test to be considered operative while you’re en route. If the engine has not received a departure test during the current run, the cab signal system is treated as inoperative for that trip, so you can’t rely on those cab indications and must proceed under trackside signals and any applicable restrictions. The other scenarios don’t cause inoperative status: if the locomotive isn’t equipped for cab signaling, there’s nothing to be inoperative; if the cab signal system is functioning properly, it’s operative; and if a departure test has been completed within the last 24 hours, the system is considered operative for the route.

Cab signals must be verified by a departure test to be considered operative while you’re en route. If the engine has not received a departure test during the current run, the cab signal system is treated as inoperative for that trip, so you can’t rely on those cab indications and must proceed under trackside signals and any applicable restrictions.

The other scenarios don’t cause inoperative status: if the locomotive isn’t equipped for cab signaling, there’s nothing to be inoperative; if the cab signal system is functioning properly, it’s operative; and if a departure test has been completed within the last 24 hours, the system is considered operative for the route.