Brake Pressure Switch Mystery???

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canada karl
Posts: 774
Joined: Tue Jan 06, 2009 3:50 pm

Brake Pressure Switch Mystery???

Post by canada karl » Sun Jun 28, 2020 9:38 am

Hello Fivers I am replacing the good brake lines from a 03/76 530i Manual to a rusted brake line 09/76 530i Automatic. The Manual car has a brake pressure switch with the two brown wires.... but the Automatic car appears to not have the brake pressure in that location?
Not to be confused with the "Brake Pressure Regulator" that goes to the rear brakes. That is in the same location on both cars.
Was the brake pressure switch for the Automatic on a later 76 relocated or does it operate in a different way than the Manual car switch? I don't see the two brown wires for the switch on the Automatic either?
Karl
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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maybeillbuyit
Posts: 228
Joined: Mon Feb 17, 2014 12:26 am
Location: Vancouver BC

Re: Brake Pressure Switch Mystery???

Post by maybeillbuyit » Mon Jul 06, 2020 4:45 pm

Karl, Where is this brake pressure switch? My car is 10/76 and I dont know if mine has one?
1977 530i another project
1979 635csi Euro "project"
1987 635csi

canada karl
Posts: 774
Joined: Tue Jan 06, 2009 3:50 pm

Re: Brake Pressure Switch Mystery???

Post by canada karl » Tue Jul 07, 2020 7:30 am

On the 03/76 it was hidden underneath the brake booster. Maybe it applied the the rear stop lights? Possibly they changed that setup the following year?
Have you removed the instrument cluster on your car? Not sure how many bolts I have to be removed to drop the column to gain access? I was able to remove the cluster to change out the speedometer but it was a bitch re installing it and keeping all the small wires for the auto trans lights in place. I can't see pulling the steering wheel being much of an advantage.
1976 530i. BMW 59 Triumph TR3A(rolling resto). 67 Triumph TR4A(salvageable). 86 900S Winter car

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