BraunAbility 37030KS Watertight Dual Microswitch Assembly
Part No. 37030KS — Replaces / Retrofits 975-3121A and 975-4121A
Fits BraunAbility Century-2 (NCL-2) Series Wheelchair Lifts
The BraunAbility 37030KS is a watertight dual microswitch adapter assembly for BraunAbility commercial wheelchair lifts. It upgrades the original 975-series switch assembly — which contains two switches in a single housing — with a weatherproof sealed replacement unit designed to withstand the moisture, road salt, and vibration exposure at the lift base location.
The 37030KS contains two switches in one assembly, corresponding to two separate safety functions confirmed in the BraunAbility Century 2 Series Service Manual:
Threshold Alarm Microswitch — detects when a person or object is in the threshold area and triggers the audible threshold warning alarm.
Partial Fold Microswitch — detects whether the lift platform has completed or begun the fold cycle and provides feedback to the lift control module.
Both functions are handled by the two switches contained in this single watertight assembly.
975-3121A vs. 975-4121A — WHICH SUPERSESSION APPLIES
37030KS is a direct replacement for 975-4121A — same mounting footprint, plug-and-play installation.
37030KS is a retrofit for 975-3121A — the 37030KS is designed to fit the 975-3121A location using the adapter hardware included in the kit, but is not a simple direct swap in all cases. Confirm that your application uses 975-3121A or 975-4121A from your BraunAbility service manual before ordering.
WHY THE ORIGINAL SWITCH FAILS
The 975-series switch assembly mounts in the lower threshold area of the lift, directly exposed to rain, road spray, snow melt, and salt. The original 975-3121A housing is not fully sealed against moisture ingress. Over time the switch contacts corrode, the internal mechanism fails, or the connector pins oxidize — producing the following symptoms:
Constant or intermittent threshold alarm beeping while the vehicle is in motion or at rest
Lift stops mid-cycle during the fold or stow sequence (partial fold microswitch fault)
Lift refuses to deploy, registering a fault related to the threshold or fold position sensor
Intermittent operation — the lift works sometimes but randomly faults as connector vibration makes and breaks a corroded connection
The 37030KS's watertight housing seals both switches and their connection points against moisture, providing a significantly more durable replacement in this exposed mounting location.
SPECIFICATIONS
Part Number (MPN): 37030KS
Alternate / Superseded Part Numbers: 975-3121A (retrofit), 975-4121A (direct replacement)
Type: Watertight Dual Microswitch Assembly (Kit/Shipout)
Number of Switches: 2 (Threshold Alarm + Partial Fold)
Housing: Weatherproof / Watertight Sealed
Dimensions: 4.50 in L x 2.25 in W x 1.00 in H
Weight: 2.00 lbs
COMPATIBLE VEHICLES
Confirmed compatible applications per TESCO Bus Parts:
2009 Braun on Ford Chassis
2011 Eldorado National on Ford Chassis
2009–2016 and 2021 Elkhart Coach on Ford Chassis
2009–2013 and 2011 Goshen Coach on Ford Chassis
2010 Glaval Bus on Ford Chassis
2013 General Coach on International Chassis
2009–2011 Starcraft on Ford Chassis
2009–2012 and 2014 Startrans on Ford Chassis
2015 Transit XL on Ford Chassis
2014 Turtle Top on Ford Chassis
2023 Forest River Van on Ford Chassis
Similar-year Ford and International chassis conversions by the same builders are very likely compatible. Verify your lift model (975-3121A or 975-4121A) from the lift's component label or BraunAbility service manual before ordering.
ABOUT BRAUNABILITY
BraunAbility, formerly The Braun Corporation, has been the industry leader in wheelchair accessible vehicles and mobility lift systems since 1963. Founded by Ralph Braun in Winamac, Indiana, BraunAbility is the most widely deployed commercial wheelchair lift brand in school buses, paratransit fleets, and cutaway bus applications across North America. All BraunAbility commercial lifts are NHTSA-compliant and ADA-certified, and genuine OEM replacement parts ensure continued compliance and reliability in revenue service.