20991438 | Volvo / Mack TSM1-A Tach Signal Module | 12V Control Unit | New Genuine NOS

New Genuine Volvo / Mack 20991438 (New Genuine NOS) — OEM TSM1-A tach signal module designed to regulate, process, and interpret tachometer signal input in compatible Volvo and Mack heavy-duty truck electrical systems. Marked VO20991438, Revision 1.2, 12V, and VGM TSM1-A.

In stock and ready to ship from Discount Parts Exchange (DPX) in Mansfield, Ohio.

Call to confirm availability: 419-522-3320

Key Specifications

• Part Number: 20991438
• Manufacturer: Volvo / Mack
• Type / Model: TSM1-A Tach Signal Module / Control Unit
• System: Electrical / Instrumentation
• Function: Tach signal processing and control for compatible heavy-duty truck systems
• Condition: New Genuine (NOS)
• Warranty: Sold As-Is, No Warranty
• Tag Details: VO20991438, TSM1-A, Rev 1.2, VGM TSM1-A
• Voltage: 12V

Applications & Fitment

Fits select Volvo and Mack heavy-duty truck platforms requiring a TSM1-A tach signal module or matching OEM control unit reference.

• Volvo heavy-duty truck electrical systems
• Mack heavy-duty truck electrical systems
• Tachometer signal processing circuits
• Instrumentation and control-module replacement applications

Important: Always verify part number, voltage, connector configuration, module revision, and system compatibility before ordering or installation.

What’s Included

• 1 × Volvo / Mack TSM1-A Tach Signal Module – 20991438 / VO20991438
• OEM control unit assembly as supplied
• Mounting hardware / fittings not included unless noted

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Shipping / Location

• Ships from our Mansfield, Ohio warehouse (419-522-3320)
• Parcel shipping available
• Warehouse Bin Location: DPX_OH_BR549_VOLVO

Heavy-Duty Solutions — Built to Perform. Trusted to Last. Discount Parts Exchange (DPX).