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WABCO · Air System
S4005001010
In stock · ships from Knoxville
This is a WABCO trailer ABS control unit known as the TCS II Basic.
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Verified fitment for 13 applications
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All confirmed applications for this part number.
Freightliner
International
Peterbilt
Other applications
Freightliner
International
Peterbilt
Other applications
Designed exclusively for 2S/1M configurations on standard trailers. Not suitable for turntables, steerable axles, dollies, or any trailer with a different sensor/modulator layout. Requires a 12V electrical system. Installation uses 2 supply ports (3/4"-14 NPT), 4 delivery ports (3/8"-18 NPT), and a 3/8"-18 NPT control port.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 16 of 34.
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It combines the electronic brain (ECU) and air modulator valve into one assembly, providing anti-lock braking on standard semi-trailers by preventing wheel lockup during hard stops. It is a 2-sensor/1-modulator (2S/1M) system designed for trailers built after March 1, 2001, commonly found on dry vans, reefers, and flatbeds from major manufacturers. You replace this unit when the trailer’s ABS warning lamp stays on, fault codes point to ECU failure, or the valve has suffered physical damage or corrosion.
Part Number: S4005001010
ABS VALVE/ECU
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside air system
