While looking at the fuse listings in the under hood fuse block, I noticed that fuse 12 was the supply for "Washer liquid heater, washer nozzle heater". Does this mean that the windshield washer fluid is heated in cold weather? I know the car had "Heated washer nozzles" as one of the features (which appears to have been dropped), but did it also have a heater in the fluid reservoir?

 

Interesting... The mirrors are supposed to be heated as well but I can't find anything that says when and for how long they will activate. Its typical documentation for German-made machinery: "The system is there and it works. That's all you need to know."

 

The main reason I'm asking is I bought the shop manual for the car and it doesn't mention either the fluid or the nozzles being heated. I does go into great detail on the heated mirrors, but is mute on the windshield washer heaters. I'm wondering if I got the right manual.

 

the crossfire will have heated reservoir and nozzle and mirrors.

 

The mirrors will only be heated when you push the rear window heater button.

 

Another question if the shop manual has errors. The only heated system of the three in this thread covered is the mirrors, and it says that the heaters are on whenever the ignition is on. By the schematic, it could be 110F in the shade and they will be on if the ignition is on.

 

Sounds like we need to check this with a volt meter! Personally, I find it hard to believe that the heaters would be on all the time. That just doesn't make sense because it would contribute to a premature failure in the heaters and cause an undue load on the electrical system. I always figured that they would a) come on automagically when the outside temperature sensor registered below some pre-determined threshold, or b) they came on with either the rear window defroster or when the HVAC selector was set to defrost the front window, or c) some combination of the above.

 

Right. The only situation when you need to heat the mirrors is when they got fogged or when there is some ice after standing in snow. Fog appears with a quick change of temperature and humidity (tunnel, garage). Ice should be removed manually. I see no need for the system to heat permanently. In the past years I used the mirror heater only a few times. Mostly when driving into a parking garage and got to back up.

 

The mirrors were heated all the time on the early production cars. There's an addendum to my owners manual stating that at some point they were changed to only be heated when the rear window defrost is turned on.