During the tractor protection valve test, within what pressure range does the manual say the control typically pops out from "normal" to "emergency"?

49 CFR 383.115(e); AAMVA CDL Manual Section 7.4.1, p. 7-4

If the tractor protection valve doesn't pop out in this range, a leak anywhere in the system could drain all the tractor's air and trigger emergency braking with possible loss of control. This is one of the manual's own explicitly stated numeric safety thresholds.