I have a 2010 Lacrosse. The rear defogger quit working. I replaced the relay with no change.
Has anyone had this problem?
I am thinking maybe a burned plug somewhere, but I don't want to tear the whole car apart if someone can point me to the most common place for this problem.

Thanks,
Richard

 

Possibly a computer reboot or/and fuse replacement; those may have a current limiting diode in circuit (acts as inline fuse) where it's a resistive load. Mirrors would be heating also with switch on I believe.

 

Thanks for the suggestions. I was finally able to get the time to reboot the computer, and checked the fuse. Still no joy. An internet search shows a fairly common problem with fried multi-connectors, but nothing on the 2010 LaCrosse specifically. It is either in the driver kick panel,driver sill, or passenger sill. Can anyone narrow it down for this specific model, and point me to the right way to get access? I have thousand of dollars worth of tools, but my experience is with 18 wheelers.

Thanks,
Richard

 

Your welcome, nobody answers anything on these forums if you seek info. Was the same way on Boss 302 Forum. Wiring through front door panels must be for the heated mirrors. Believe those would be parallel circuits to save on wiring and main defroster circuit would run through a front to rear harness? Heating tapes would have some sort of rubber boot connection from wiring to heating strips and possible even those are interconnected, from the ones I've seen anyways.

But also, those may have some type of thermostatic control to operate the relay? Don't those have auto shut off and/or hi-limit switches after being on for so long? Would imagine heating elements as such would self destruct if on constant. Just speculating on things from the past, one time I had to repair broken wires on a hatchback rear defroster we had but was pretty straight forward.

Forgot to ask but do the heated mirrors still work? Would narrow things down there....

 

Do you have a wiring diagram / schematic ?

God bless
Wyr