Standard Ignition TS-581 Engine Cooling Fan Switch

Engine Cooling Fan Switch for BMW Applications

The Standard Ignition TS-581 is an engine cooling fan switch built for direct-fit service on select BMW models. It uses a plug-in attachment method, a female oval connector, and a 3-pin male terminal layout to support a clean electrical connection in the cooling system.

Compatible With 1995-2000 BMW 740i, 740iL, and 750iL applications, plus 1997-2000 BMW 528i and 1997-1998 BMW 540i and 740i models. The TS-581 is a 12-volt switch with a 14MM x 1.50 thread size and an open-at-idle design.

Key Features

• Standard Ignition TS-581 engine cooling fan switch
• Plug-in attachment method with 1 female oval connector
• 3 male pins for the terminal interface
• 12-volt electrical specification
• 14MM x 1.50 thread size
• Open at idle configuration
• Metal housing with brass and plastic finish
• White color/finish

Detailed Product Overview

The TS-581 is an oval-shaped engine cooling fan switch designed for BMW cooling system service where the fan control circuit uses a threaded, plug-in sensor style. Its metal housing, brass and plastic finish, and 3-pin terminal arrangement support a straightforward replacement for the original switch location. This part number, TS-581, is also referenced for select OE and aftermarket cross applications, including BMW 61318360857, FS327, SW3011, and TFS692.

For BMW 528i, 540i, 740i, 740iL, and 750iL coverage, this switch provides the correct thread size and connector style for the listed applications. The TS-581 is a practical choice when servicing a BMW cooling fan switch that uses a 14MM x 1.50 threaded mount and a female oval plug connection.

What This Part Helps Address

• Cooling fan that does not cycle on at the proper temperature
• Fan operation that is inconsistent or intermittent
• Faulty temperature-based fan control signal
• Electrical connection issues at the cooling fan switch
• Replacement needs for a worn threaded fan switch on BMW cooling systems

Installation Notes and Tips

Verify the connector shape, terminal count, and thread size before installation. The TS-581 uses a plug-in connection with a female oval connector and 3 male pins, so the mating harness must match the original configuration. Confirm the vehicle’s cooling system specification and mounting thread as part of the replacement process.

Fits 1997-2000 BMW 528i, N/A. Fits 1997-1998 BMW 540i, N/A. Fits 1997-1998 BMW 740i, N/A. Fits 1995 BMW 740i, N/A. Fits 1995-1998 BMW 740iL, N/A. Fits 1995-1998 BMW 750iL, N/A.

Quality Assurance

Standard Ignition is a recognized aftermarket brand for electrical and engine management service parts. The TS-581 is built with a metal housing and a brass/plastic finish to support replacement use in the specified BMW cooling fan switch applications.