[Buffnav]

2004 Passat has an electrical plug on the Battery (positive) cable (see pictures). I think in a rush in which I had to pull the battery a few months ago, I didn't catch whether it was connected or not. I've looked for the female plug connection within the radius of the plug's cable, but cannot find anything it might connect to. Coincidentally, I'm having heat problems with Supply Voltage (214) codes as well as Footwell Defrost Flap Servo (25b) and (4F8) codes. Any comments appreciated.

 

[VAGguy]

it doesn't go to anything on US cars. Its been covered many times but I don't know if anybody figured it out. My 04 has the cold weather package and everything so its not related to that.

 

[Buffnav]

Thanks so much, thought I was nuts though with such an obvious disconnect...though I was hoping it might relate to the heater problems.

 

[Zach440]

An educated guess: it may be a power lead for the heated windshield that is available in parts of Europe...E

 

[Passat2.8]

I believe it is for the heated windshield:

Harness:
http://www.passatplus.de/umbauteile/scheiben/3B1971271N.jpg
Install:
beheizbare Frontscheibe

 

[scotts13]

(GRIN) Puzzled me, too - and my VW dealer. His theories were: Connection for a trickle charger for use in shipping - OR - Monitor for the water extraction filter in european Diesel-engine cars.

 

[Passat2.8]

They do not trickle charge during shipping-it is too risky.
The urea filtration system was not implemented on the B5/B5.5 chassis.

 

[Zach440]

...and just to round out the discussion, that plug is supposed to go to the brake fluid reservoir---in the photo supplied from Passat2.8 it is the black plug at the very top of the photograph and is labeled "Brake Fluid Reservoir" --German "Bremsflussigkeitsbehalter"--- I guessing now but it either monitors the brake fluid level or keeps the brake fluid warm on those Lapland nights!! E

 

[Zach440]

...and just to round out the discussion, that plug is supposed to go to the brake fluid reservoir---in the photo supplied from Passat2.8 it is the black plug at the very top of the photograph and is labeled "Brake Fluid Reservoir" --German "Bremsflussigkeitsbehalter"--- I guessing now but it either monitors the brake fluid level or keeps the brake fluid warm on those Lapland nights!! The two plugs that are marked 'frontscheibe links/rechts are the electrical plugs that plug into the connectors at each side of the windshield providing current to the element that heats the windshield...E

 

[VAGguy]

There's already a level sensor in the second pic (upper right hand corner).

 

[Zach440]

....which is in the center of the first photograph sitting above the battery tray, moved from its position in the first photograph--I believe that if you inquire of Buffnav, he will indicate that he moved the connector in question, taking each photograph with the connector in a different position---I stand by my original premise...

 

[VAGguy]

I still stand by my answer which is correct. That mystery plug comes out of the shrink tubing at the end of the battery cable. It hangs on the underside of the battery compartment cover. I have it on mine, it definitely does not connect to the brake fluid reservoir in any way on North American models. It also has a connector plugged into it with blunt cut wiring.

What I am saying is that it is not for the level sensor.

If it were for a fluid heater, shouldn't it also, in theory, show up in Canadian models?

 

[Buffnav]

Sorry Zach440, I did not move the electrical plug. The second photo shows another plug already connected to the Brake Fluid reservoir you are referring to.

 

[Passat2.8]

The only options that I know of over in Europe that would be contained in that harness are the heated windshield and the DWA Siren which is a three-pin connector and I happen to have it.


Beheizbare spritzdusen-Heated windscreen washers
Frontsheibe links/rechts-heated windscreen left/right
Wishermotor-washer motor
Bremsflussigkeitsbehalter-Brake Fluid Level Sensor
Relaissockel-Relay for the heated windscreen
The large lugs are battery connections

By the way, how many wires go to the dead-end plug?

 

[Passat2.8]

Just looked this up on a parts site and it says some vehicles had a battery isolation relay, maybe that's it?

 

[Mtech]

If it were for a fluid heater, shouldn't it also, in theory, show up in Canadian models?

Nyet, there is no brake fluid heater in Kanukistan, we use 50% Vodka 50% Maple Syrup for Winter, ie September to July.

 

[2stroke]

My 04 has the cold weather package and everything so its not related to that.

I have never heard of a Cold Weather package on a B5/B5.5
Please explain !

 

[VAGguy]

maybe it is standard in your part of the world but to us, it's heated seats, heated washer nozzles and I believe heated mirrors.

 

[captainfantastic]

I have never heard of a Cold Weather package on a B5/B5.5
Please explain !

Heated windshield, seats and jet washers

If it were for a fluid heater......

Which never existed...

If the plug is for the heated windshield, there must be a similar one (one for each side, located in the windshield´s lower edges)

 

[nolesfan]

If it were for a heated windscreen (which it isn't), wouldn't the glass have tiny little elements in it like the rear defogger does? Of course it would be smaller and built into the glass... The only reason I mention is I know Range Rovers (at least the old round headlamp ones) had this...