Mystery Wire

[Jim75911S]

This conductor is coming out of the tunnel and has an outer cover, the wire is brown with a white strip. The car had the master cylinder behind the brake pedal originally. I have relocated brake light wires to the booster assembly but I dont remember where this wire attaches and cannot find it in any pictures. Any help appreciated. Jim

[Quicksilver]

Year and model would really help.

[Jim75911S]

1975 911s It was long enough to reach the brake light switch but there was not a terminal for it. Also it does not show continuity to ground and applying 12v to it did not illuminate anything.Sooooo?

[ossiblue]

I don't have a diagram for 75 but seat belt warning wires are brown/white stripe. Does your belt warning system still work?

[Jim75911S]

I'll check that out, but if I remember correctly all the saet belt wires are not in the tunnel but are run in a separate group down the passenger side outside of the tunnel. This wire is on the inside. The only other wire that has the same outer jacket is the emergency brake ground and it is brn/yellow. I have checked it for continuity no dice.

[techman1]

Did that year have a warning light when handbrake was on?

[Flat Six]

Don't recall if 75 has this, but looks like the wire that connects to the BF reservoir cap to indicate low BF level.

HTH

[Jim75911S]

The wire for the brake fluid level would have been in the trunk area would it not. This wire goes into the tunnel. When I pull on it I get a rattle inside. Also I have both the brake light switch pair and the brake warning pair located. Would the brake fluid level wire be entering the main wiring harness in the tunnel? I'm stumped.

[Zeke]

I've have to look at a diagram to be sure, but any brown wire is usually a ground. Some grounds are open until a circuit is made, so that may be why you don't get continuity. Try checking the continuity while operating the hand brake and brake pedal.

[Jim75911S]

Thanks Milt already tried that, not hand brake for sure.

[saint914]

Sportomatic wire to gearchange for clutch operation?

[Jim75911S]

Manual transmission. This wire is holding up interior completion. I guess I will extend it up to the trunk area. At least from there I can work with it. The length of it leads me to believe it went to the brake switch or in that area. The master cylinder is in there now. Thanks for the help! Jim

[ossiblue]

This really is a mystery. Does your 75S have a worn brake pad warning system? That could be an open ground wire as Milt suggested that goes to ground when the rear pads are low--if the car is so equipped.

[jstobo]

Brown with white stripe wire is switched ground. In other words they connect to a switch which when it closes providing a ground illuminates an indicator light. Earlier cars had a switch on the master cylinders that indicated brake failure if the master cylinder failed. It may go there. I would ground the wire with the ignition on and see if anything lights up. Good luck.

[LM3929]

Is it possibly to the cruise contol switch in the tunnel?

Lorne M.

[Jim75911S]

No brake pad sensors. Both brake light and other pair that connect to the MC accounted for. However the brake fluid cup has an electrical termination on it, I do not have a conductor for it. I don't remember if the 75 MC had one on it but again it was located in the trunk area not in the floor board. This wire was connected near or to the pedal assembly. I will try grounding it when the time comes. Thanks for the input!

[techman1]

If it was a later car, I would think the clutch switch to disengage the cruise control.

[Laneco]

Between the seats, near the heater controls - does your car have the little plastic panel that illuminates? Is this the wire for that?

(random guess - I don't have one that year)

angela