Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
sorry for the delay.............Greetings...... “Hi, I’m Don (aka MOLurch) and I look forward to helping you!”.For the Heating Element to work, you have to have Voltage + & Ground -The BCM (body control module) provides a Ground signal to the Element Relay to activate the RelayThe Relay then provides Voltage + to the Grid / Heating ElementThe Grid is Grounded to G410G410 is located on the Right Rear Pillarclick Attachments below
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I provided you with the Schematics to check the complete circuit Ground - & Voltage +You posted:there is 12 volts across the two terminals
You have to have a Ground - at one terminal when the Relay is activatedCheck Relay to see if it has Voltage + & Ground & if it activates.
you need to check Ground at the Grid, as the BCM controls the Relay which provides the VoltageThe BCM is cued from the Door Switches of the Rear Door / LiftgateIF the BCM does not get a signal from the Switches in the rear, then the Relay will not come onThe Door Mirror Heat is also controlled via the BCMShould be Voltage + on the ORANGE wire of the Door Module to the Mirror & Ground - on the BLACK wire
here is diagram
click Attachment below
grid = De-icer film on the glass or what you called the heating ribbons