Digitrax LT5C | 2-Pack LocoNet Cable Tester Module - Diagnose RJ12 Cables & LocoNet Bus Issues | Multi Scale

The Digitrax LT5C is a handy LocoNet diagnostic tool — it plugs into any LocoNet jack and uses an LED indicator to verify that the cable, the jack, and the LocoNet bus power are all wired correctly. The LED lights up only when ALL six pins of the RJ12 jack get correct signal — making it the fastest way to find a bad cable, a miswired UP5/UP6 panel, or a broken LocoNet run before you spend hours debugging your throttles. This 2-pack gives you one to leave at the start of your bus and one to walk around with.

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• 2 LT5C tester modules per pack — one for each end of the bus, or one for the home base and one to walk the layout.
• Plugs into any standard Digitrax LocoNet RJ12 (6P6C) jack.
• Single LED indicator lights when all six pins are wired correctly — instant pass/fail.
• No batteries, no setup — passive diagnostic, draws power from LocoNet.
• Compact key-fob sized housing, slips into any toolbox or pocket.

What does it test?
It verifies all six LocoNet pins are correctly wired AND that the LocoNet bus is delivering signal at that jack. If the LED is dark, you have either a bad cable, a miswired UP5/UP6 panel, an unplugged section, or a dead command station.

Will the LT5C find a specific bad wire?
Not exactly — it gives a pass/fail on the whole jack. To narrow down which pin is bad you'd plug it into successive jacks along the bus to find where the fault starts. For pin-by-pin testing, Digitrax also makes the LT1 (more detailed but discontinued in some regions).

Do I need two?
Two-pack lets you leave one at the command station to confirm the bus is alive, then walk the layout with the other to verify each UP panel and run as you set up or debug. Many builders also leave one permanently plugged into a hard-to-reach drop point for instant verification.

Will it work on non-Digitrax DCC systems?
No. LocoNet is Digitrax-specific. NCE, MRC, and other DCC systems use different cab buses.