Circuit/System Description

WARNING: This page is about a different car, the 2007 Suzuki XL7. However, it is still accessible from the selected car via links, so may be relevant.

When you depress the rear defogger button, voltage is supplied to the DEFOG relay coil and the HVAC control module also illuminates the rear window defogger indicator. Battery positive voltage is supplied at all times to the DEFOG relay switched input and the DEFOG relay coil is always grounded. This allows battery positive voltage from the relay switched input through the switch contacts and out the relay switched output to the rear window defogger. Ground for the rear defogger grid is provided by G401.

When you start the engine and press the rear defogger switch for the first time, the defogger cycle lasts for 15 minutes. Further operation results in 7.5 minute defogger cycles. The defogger cycle resets to 15 minutes when you cycle the ignition to the OFF position and then to the ON position.