Description
WABCO ABS ECU/VALVE ASSEMBLY (2S/2M – TRAILER MODULE)
PART NUMBER(S):
Fleet Products: S400 500 1020 (New) | Replaces OE: WABCO: S4005001020, S400 500 1020, 4725005211, S4725005211 | Freightliner: TDAS4005001020 | Great Dane: 40502932 | Hyundai: 10008470 | Kenworth: S400-500-102-0 | Manac: 22801003, 228-01003 | Meritor: S4005001020, S4005001027 | Peterbilt: S400-500-102-0 | Stoughton: 46040401300 | Utility Trailer: ESS4005001020, 3-9350-074, 393500074 | Vanguard: 1ABS00014, 2ABS00014 | Volvo: TDAS4005001020, WAB4005001020 | Wabash: RWW4005001020
DESCRIPTION:
Model: Enhanced Easy-Stop ABS Modulator Valve Assembly (2S/2M)
Vehicles: Mack, Manac, Peterbilt and standard trailers manufactured after March 1st 2001 equipped with 2S/2M WABCO ABS systems
Applications:
• ABS relay modulator valve with integrated ECU – used in standard trailer ABS systems.
• Direct replacement for WABCO Enhanced Easy-Stop and TCS II Basic systems.
• Maintains braking stability by modulating brake pressure and preventing wheel lock-up.
• Plug-and-play upgrade/replacement for legacy ABS 2S/2M trailer units.
• Supports TCS II (traction control system) in compatible trailers.
• System Type: 2S/2M (2 sensors, 2 modulators)
• Voltage: 12V
• Max Operating Pressure: 13.0 bar
• Includes: ECU (S446 850 600 0) + Dual Modulator (S400 850 602 0)
• Temperature Range: –40°C to +65°C
• Port Threads:
– Control Port: 1/4"-18 NPT
– Delivery Ports: (4) 3/8"-18 NPT
– Supply Ports: (2) 3/4"-14 NPT
• Mounting: Flange-mounted ABS relay valve
CROSS-REFERENCE(S):
S4005001020, S400 500 102 0, TDAS4005001020, 40502932, 10008470, S400-500-102-0, 6300-4005001020, 22801003, 228-01003, 4005001020, 400 500 102 0, 815-4005001020, 650-S4005001020, S-27491, 670-S27491, S27491, 8235-S4005001020, 46040401300, 52733, 3-9350-074, WAB4005001020, TDA-S4005001020, 4005001029, 2ABS00014, RWW4005001020, 170.S4005001020
A cross-reference listing means this part should be a suitable replacement for the part numbers listed. Please confirm all ports and dimensions match your application before installing.
IMPORTANT INSTALLATION NOTES:
✔ Mount on the air tank using a 3/4" Schedule 80 hex nipple or on the frame using Grade 8 hardware.
✔ Ensure the exhaust port faces downward and plug all unused ports with approved thread sealant.
✔ Use 5/8" O.D. minimum supply tubing and secure all air line connections.
✔ Route sensor and power cables with adequate strain relief; avoid tight bends and overtightened tie wraps.
✔ Secure cables every 8–18" and leave sufficient slack for suspension movement.
✔ Perform end-of-line ABS testing after installation and verify proper sensor orientation and ABS indicator lamp operation.
Warranty Information
