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OOSC, Part II, Item 1. Brake Systems, j. Low Pressure Warning Device

Entry DateFebruary 25, 2010
Issue Number10-006-VEH
NameCharles Longfellow
AgencyTexas Department of Public Safety
AddressP.O. Box 4087Austin, TX, 78773United StatesMap It (opens in a new tab)
Phone512-424-2880
Fax(512) 424-5262
Email[email protected]
CommitteeVehicle Committee
StatusClosed
Summary of Issue

The April 1, 2009 North American Standard Out-of-Service Criteria (OOSC) states a motor vehicle is out-of-service if the \"Low Pressure Warning Device is missing, inoperative, or does not operate if either the primary or secondary reservoir is at 55 psi (379 kPa) and below, or 1/2 of the governor cut-out pressure, whichever is less.\" The question arises, if the visible warning signal activates at 55 psi for 15 seconds then goes out while the pressure gauge continues to display 55 psi, would this constitute an out-of-service condition? In other words, the low air visible warning fails to provide a continuous warning signal while the air pressure system is low on air. FMVSS 121.5.1.5 requires the signal to be a continuous warning to the driver if the service reservoir system is below 60 psi. Because the warning signal is not continuous, the device is defective. However, the OOSC does not address a defective low air warning device.

Justification or Need

To provide a better definition for a defective Low Pressure Warning Device.

Request for Action

We would like to add the words ?defective? and or ?continuous? to Low Pressure Warning Device.