Switch in windscreen frame latch: Notes

WARNING: This page is about a different car, the 2001 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.

To ensure that the soft top is secured to the windscreen frame when the car is being driven and released when being operated, there are two reed switches that detect whether the soft top is mechanically locked to the windscreen frame or not.

The switches consist of a reed switch and a permanent magnet on each side. The reed switches are located in the latch fittings in the windscreen frame. The permanent magnets are located by the lock hooks on the first bow and their magnetic fields affect the switches when the first bow is locked to the windscreen frame.

Fig 1: Identifying Windscreen Frame Latch Switch Connection

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Fig 2: Windscreen Frame Latch Switch Operating Circuit Diagram

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Pin 3 on the left switch is connected to control module pin 34 and pin 2 is connected to grounding point G36. Pin 3 on the right switch is connected to control module pin 19 and pin 2 is connected to grounding point G36.

When the ignition is turned to the ON position, the control module outputs B+ via a 1 kOhm resistor to the switches from pins 34 and 19, and when the soft top locks the permanent magnets activate the switches which then close and the control module inputs are grounded.