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Pro-Par · Air System
THO-313
In stock · ships from Knoxville
The Pro-Par THO-313 is an ABS Electronic Control Unit (ECU) for trailer air brake systems, specifically the top half of a Meritor WABCO MBS-1 style 2S/1M (2 Sensor / 1 Modulator) module.
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Verified fitment for 1 applications
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Other applications
Other applications
This is the top electrical half of a 2-Sensor/1-Modulator ABS unit. It is not a standalone complete valve; it requires the existing or separately purchased MBS-1 modulator valve (bottom half) to function.
Part data verified against 4 catalog sources
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It is sold as the top electrical half only and includes a pre-attached 168-inch power cable. This unit is commonly replaced when the ABS warning lamp stays on, during a diagnostic trouble code indicating an ECU failure, or when the electrical connector/cable assembly is damaged, as it does not include the lower modulator valve portion.
Part Number: THO-313
ABS ECU, MBS-1
Unit: ea
Dealer: Knox Trailers
Compatibility, alternatives, and more
Parts commonly needed alongside air system