My 2007 GMC 2500 new body style comes from factory with heated mirrors and when you turn the rear defog on is suppose to heat the mirrors,but it doesn't.Rear window defog works fine. Relays and fuses are all good. Someone was suggesting it may be the control module. Does anyone no where this is located? Or any other help would be greatlly appreciated. Thanks
Could have a DDS an PDS .depends on what RPO code yours has >
Outside Mirror Description and Operation (with RPO DL3)
Or
Outside Mirror Description and Operation (without RPO DL3)
Without
Heated Outside Rearview Mirror Operation
The REAR DEFOG relay controls the operation of the heated outside rearview mirrors. When rear window defogging is requested, the REAR DEFOG relay is energized and B+ is applied to the supply voltage circuit of the mirror heater element, located in the mirror face. A constant ground is also applied to the mirror face. Current will pass through the mirror heater element, warming the mirror, so long as the rear window defogger is commanded ON.
With
Heated Outside Rearview Mirror
The DDS and PDS control the activation of the mirror heaters. Upon receiving a serial data message indicating a request for heated mirrors, the DDS and PDS, will apply voltage to the mirror heater element supply voltage circuit. The mirror heaters will remain active until a new message is received indicating rear defogger is to be deactivated.
The power mirror system consists of the following components:
• Driver Door Switch (DDS)--An electronic control module with integrated switches and requires programming when replaced
• Passenger Door Switch (PDS)--An electronic control module with integrated switches, requires programming when replaced
• Power Mirror Direction Switch--Integrated into DDS and is a four position momentary switch that provides a signal input to the DDS for up, down, left/extend and right/retract with a mirror switch activation
• Mirror Select Switch--Integrated into DDS and is a three position switch that allows the operator to select the left or right mirror and also a neutral/fold position
• Mirror Extend/Retract Switch--Integrated into DDS and is a two position switch that allows the operator to select the mirror extend or mirror retract position
• Left Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Right Outside Power Mirror--Contains both the vertical and horizontal mirror motors
• Body Control Module--An electronic control module that requires programming when replaced, serves as the power mode master and is the main message handler
• Horizontal and Vertical Position Sensors, if equipped with memory mirrors--Supplied a 5-volt and low reference by the DDS/PDS and provide a variable voltage signal to the DDS/PDS that is proportional to mirror position
• Folding Mirror Motor, in each of the outside mirrors, if equipped with power fold mirrors--Provides extend and retract movements of the mirror and is serviced as a complete mirror assembly
Your best bet mite be to take to a qualified repair shop , i really don't think you'll be able to do anything with it.
Do you have wiring diagrams so you know which wires to test ,do you know how to do electrical testing ?
The Driver Door Switch (DDS) and Passenger Door Switch (PDS) supply voltage to the outside rearview mirror heater elements upon receipt of a serial data message from the HVAC module indicating that the rear defrost system is active. The door switch supplies B+ through the driver/passenger mirror heating element supply voltage circuit when a request is seen. Ground is applied through the driver/passenger mirror heating low reference circuit.
SOURCE: How to replace side mirror on 1996 GMC Sierra?
See Figure 2
Fig. 2: Outside mirror-below eyeline type
Hope this helps .. if not feel free to contact me
SOURCE: 2005 GMC Yukon Denali XL - Climate Control issue-
Are you aware of any codes that may stored in the body control module and do you hear a clicking or ticking noise in the rear?
268 views
Usually answered in minutes!
×