I just now noticed after three years, that my rear passenger side quarter window has no defroster grids, butthe drivers side does. Whats that all about?

(03 limited Full size)

 

I vagueely remember something on that rear window too. I always thought it was for radio but that did not make sense. Could it be the electronic compass?

 

I just checked the defogger schematics for the 03 montero and there is only 3 heating elements in the circuit - each side mirror and rear glass. Anything in the side glass does not appear to be a defogger...

 

Looks like its probably a glass antenna AM radio. AM antennas have more gain when they are like a loop where FM is a dipole (like the mast one that extends and retracts. This can be verified by tuning the radio to a weak AM station and interfering with the operation by putting metal up to the glass antenna to see if reception changes. Great find! Now Im curious!

 

The Stock Radio uses both antennas with a "Diversity" System, switching between and combining signals to improve reception as conditions vary while you drive.

I am in the middle of sourcing a new radio for mine and found out that I will have to abandon this setup with an aftermarket radio, a well, I doubtI will notice the difference in reception.

 

Thanks for the information. I read your post and then found the following on the web:

"A few of the premium factory equipped car stereos have diversity antenna reception. Only two after market car radio manufacturers currently offer it. The diversity system uses two antennas on the car and constantly compares reception on both, switching the better one to the radio. This eliminates about 80-90% of the multi-path picket fence distortion of a moving vehicle."

Wow - cool - I did not realize that the OE Infinity had this feature. Cool - The Monty continues to impress me - even after 4 years of ownership. Maybe you can find an aftermarket system with Diversity if that is an important feature for you...