Interpretation ID: aiam1062
Chief Engineer
Automotive Products
Wagner Electric Corp.
Wagner Division
11444 Lackland Road
St. Louis
Missouri 63141;
Dear Mr. Kourik: This is in reply to your letter of February 16, 1973, requesting a interpretation of paragraph S5.4.1 of Federal Motor Vehicle Safety Standard No. 105a.; Answers to your questions are as follows:>>>1. The reservoi configuration in your Sketch No. 1 would meet the requirements of S5.4.1 for compartmentalized reservoirs. We have provided a similar interpretation to General Motors Corporation on this point, which is enclosed for your reference.; 2. Since the configuration of your Sketch No. 1 conforms to S5.4.1, single fluid lever sensing device is acceptable; 3. The configuration shown in your Sketch No. 2 would not comply wit volumetric requirements of S5.4.2 since your 'reserve' fluid volume plus 'protected' fluid compartment 'A' and 'B' volumes would not be equal to the total volume required by S5.4.2. S5.4.2 requires a volume for *each* reservoir equal to the fluid displacement resulting when all wheel cylinders or caliper pistons serviced by the reservoir move from a new lining, fully retracted position (etc) to a fully worn, fully applied position. Thus, if this final condition existed on both subsystems, one subsystem would not have the specified fluid available.; 4. The configuration depicted in your Sketch No. 3 would meet th requirements of S3.4.1 and S5.4.2 as well as S5.3.1(b) assuming the indicator lamp would be activated at or above the 25 percent level of fluid volume.; 5. The configuration shown in your Sketch No. 4 would meet th requirements of S5.4.1 and S5.4.2 as well as the requirements of S5.3.1(b) with the same assumption that the lamp would be activated at or above the 25 percent fluid volume level<<<; Sincerely, E.T. Driver, Director, Office of Operating Systems, Moto Vehicle Programs;