This bulletin applies to 2013-2019 Cadillac ATS, 2016-2019 ATS-V, 2014-2019 CTS Sedan, 2017-2019 XT5, 2013-2019 XTS, 2015-2019 Escalade 2WD and 4WD, 2013-2019 SRX and 2014-2019 ELR vehicles. Some customers may comment that an oily substance is found on the inside of the windshield surface and appears to be leaking from the rear view mirror area.
The oil/fluid is from the gel pad of the moisture sensor. The fluid can separate and leak due to heat loads. The sensor should only leak one time and the leakage will not affect the performance of the sensor.
Clean the glass surface and sensor bracket with an isopropanol alcohol wipe until the surfaces are clean, then re-install the moisture sensor.
Test the sensor by placing the ignition in the run position and rotating the wiper switch intermittent (delay) band fully forward. Once the wipers wipe once, apply water to the outside of the windshield in the area of the sensor with a spray bottle.
After one or two sprays, the wipers should wipe.