All of the above I believe is related! I'll try to explain.

There's been a drain on the battery. It's coming from Fuse #4 (which is the only hot fuse when the car is off.) When I start the car for the first time during the day, it's dead.

Until I can track this down I've been pulling fuse 4 when I park the car.

Around the same time that this started happening my instrument panel lights stopped working entirely. I know the rheostats on these cars (and every Volvo I've owned actually) are kinda flimsy, but I've never had one just die with out warning. (Usually I can at least make the lights flicker on an otherwise dead rheostat).

Poking around under the dash to see if I could find something, I found a loose wire, pictured below (drivers side):



(I apologize for the poor quality of the picture, My cell phone is the only camera I have access to at the moment.)

The red arrow shows the wire I discovered not connected to anything. It's a brown wire. It comes out of the sheath where the wires that connect to the black 6 pronged connector come from. Here's another picture that shows where the wire comes from a bit clearer.



The red arrow again shows the wire I discovered. The blue arrow shows the black connector I was talking about in the paragraph above.

What does this brown wire do? I looked at a wiring diagram of the car but didn't see any brown wires associated with the rheostat. Is it possible this is leading to my dead battery? Is the wire related to my dead battery / rheostat?

Thanks as always.
--
Formerly 'HearToTemptYou'

Dylan;

From memory, I believe Cameron has it right...it's a spare wire...I'd just tape it up at both ends (under the dash at the 6 Pin connector, and in the trunk- don't recall where it exits the sleeving at the moment) to assure it doesn't inadvertently touch anything...no it most likely doesn't have anything to do with your Discharged Battery. Instrument lights are fuse by F3 and varied by Variable rheostat in Lights Knob...these like to go intermittent...I just bypass rheostat and tie connections together for maximum instruments brightness.

Good Hunting


Here are some of my notes on Parasitic battery discharge:

If your car battery discharges unacceptably quickly you must fist determine if this is caused by an excessive inadvertent load external to the battery (i.e. headlights left ON), which is not its own fault, but a driver error, OR a problem internal to the battery (i.e. shorted cell). The best way to do this is by process of elimination...disconnect (the fully charged) battery, leaving it disconnected overnight, and reconnect it just before the next mornings starting attempt. In this manner, everything external to the battery has been eliminated from consideration. If the battery remains fully charged and starts car just fine, problem is likely external to battery (like maybe on that Fuse 4 battery powered circuit on a 122). If on the other hand, battery is weak or discharged, an internal problem exists within the battery. This is quite possible and not as uncommon as one might think. (Or it wasn't fully charged to begin with...clearly another issue)

If you don’t have the luxury of being able to wait overnight, and you must narrow in a parasitic load external to the battery immediately, disconnect the positive battery cable and wire a multimeter, set to measure current, in series. With all loads OFF and only normal battery powered loads functioning the maximum current one should see would be about 50mA. These low level loads include clock, station presets and memory of a stereo, alarm etc. * A battery with a full charge can supply these miniscule loads easily for a week. More than 50mA will start to become a significant load and this should be located and eliminated...do this by pulling Fuse 4, and observing what the battery load current drops to.

* The electronic power switches of high power automotive audio amps are also well known for doing this...they will also discharge the battery while “OFF”. This is because their control circuit is actually powered and active, looking for a control signal from the stereo head to power up the output stage. This is similar to a modern television...the display may be OFF, but the control circuit is powered up all the time...it needs to be...because it is constantly looking for an input signal from the remote. Eliminate problems caused by this with a relay which truly drops power when IGN is OFF.

Similarly, any device with a soft touch ON/OFF switch will typically exhibit this kind of action...If you have one of these devices and don’t use it for a month, you can be guaranteed to have to replace its batteries before the next time you use it...because for that entire month, while for instance the walkie-talkies were sitting on the dresser, that control circuit was powered (minusculy, but nonetheless powered and drawing battery power) and waiting with baited breath for you to push that soft touch ON button...this just another example of wastefulness and woosification of America i.m.o.! Give me a toggle switch any day, which truly removes power when in the OFF position instead of this soft touch crap! Remove batteries from these devices when not in use!

That brown wire is essentially an 'extra' wire that was installed in the wiring loom at the factory. It leads to the trunk, where it doesn't connect to anything. It's handy if you decide to install an electrical accessory of some kind - like a rear window fan or defroster; or a courtesy light in the trunk.

Best,

Cameron
Rose City

My son's '69 has that same brown wire in the same location, bare on the end, identical to yours. I think Ron Kwas knows what it is.

Cheers,
--
Barry -- 1967 122S 'Betty'

I have a '66 122s. I'll look tomorrow for that wire. To the best of my knowledge, all the brown wires go to ground. If you have a test light, connect it between the negative battery post and cable. If it lights, you have a draw on the circuit. This will allow you to disconnect things one at a time until the light goes out. When the light goes out, you will know where the draw is coming from. If you need more help. just ask.