Pennsylvania Auxiliary Lights: One Pair Only, LED Strips Legal Only on Motorcycles

The controlling numbers sit in PennDOT's inspection regulation. Under 67 Pa. Code § 175.66(l), auxiliary driving lamps and fog lamps may be installed on a passenger vehicle or light truck only if they are mounted on the front, spaced at least 20 inches apart from center to center, no more than 42 inches above the surface the vehicle stands on and no lower than the lowest chassis part, and aimed with the vehicle and lamp assembly straight ahead so the beam is not above the horizontal centerline of the lamp at 25 feet. Paragraph (5) caps the quantity: a vehicle may have only one pair of approved auxiliary driving lamps and fog lamps. Paragraph (6) forbids placing them in front of a required lamp, which rules out the common bumper installation that sits ahead of a turn signal or parking lamp.

Switching is regulated as tightly as position. Auxiliary driving lamps may not be substituted for headlamps and may only be used with the high beams. Fog lamps may not be substituted for headlamps either, though rear fog lamps are acceptable when originally installed or offered as optional equipment. The annual safety inspection enforces exactly these points: 67 Pa. Code § 175.80(a)(9) directs the mechanic to check the lamps and lenses and reject the vehicle if auxiliary equipment is placed on, in or in front of a lamp, if the fog lamps operate with the high beams or are substituted for the low beams, if the auxiliary driving lamps operate with the low beam or alone, or if a lamp shows a color contrary to the lighting chart.

Brightness has a ceiling. Section 175.66(d) caps the total candlepower for headlamps and auxiliary lamps combined at 150,000, measured against minimums of 7,500 candlepower on low beam and 10,000 on high beam in § 175.66(c). A pair of modern high-output pods added to a factory headlamp system is what pushes a Pennsylvania vehicle over that line.

Decorative lighting is handled by a single sentence. Section 175.66(h) provides that a lamp not enumerated in the section and not located as described in Tables III, IV and V is prohibited unless available as original equipment, and adds that an illuminated sign is prohibited except on taxicabs, ambulances and trucks. There is no permissive list to argue into, so ground effects, interior-spill LEDs visible from outside and grille strips fail by default rather than by a specific ban. The regulation also polices color at the edges: guidance laser systems used for line painting and snow plowing, authorized under § 175.66(l)(11), may not emit red or blue light visible to other motorists.

Off-road lamps are the recognized workaround, with conditions. 75 Pa.C.S. § 4303(f) permits off-road lighting lamps on the roof or roll bar so long as they are covered with an opaque covering that prevents any light being emitted while the vehicle is on a highway or trafficway, and § 175.66(l)(9) adds that the vehicle must carry a switch that tells the driver through a pilot light when those lamps are on. Snow plow lamps are separately allowed by § 4303(g) and § 175.66(l)(8), wired through a double throw switch so both sets cannot operate at once, spaced at least 20 inches apart, symmetrically placed about the vehicle centerline, and aimed so the high intensity portion of the beam is never higher than 42 inches above the surface at 75 feet ahead.

Motorcycles are treated as a different problem. Act 50 of 2006 added 75 Pa.C.S. § 4310, which permits auxiliary lighting on a motorcycle to protect the driver, and names blue dot illumination, standard bulb running lights and light emitting diode pods and strips. The inspection regulation follows: 67 Pa. Code § 175.146(h) carries the ornamental lamp prohibition for motorcycles but excepts auxiliary lighting added under § 4310. A rider can therefore run LED strips that would fail a car at the same inspection station.

Flashing and revolving lights sit outside the auxiliary lighting rules entirely, in 75 Pa.C.S. §§ 4571 and 4572. Red is reserved for emergency vehicles, and the combination of red and blue only for police, sheriff, coroner, medical examiner and fire police vehicles. Pennsylvania then does something few states do: § 4572(a) lets ambulance personnel, volunteer firefighters, certified volunteer search and rescue organization members, and owners and handlers of dogs used in tracking humans each equip one personal vehicle with no more than two flashing or revolving blue lights, provided their names have been submitted to the nearest station of the Pennsylvania State Police on a list signed by the department or organization head, and the lights are operable by the driver from inside the vehicle.

§ 4303(f), carrying a fixed $100 fine on conviction. § 6502(a) applies and sets a $25 summary fine, with § 6502(b) extending the same treatment to violations of PennDOT regulations such as Chapter 175. § 4107(a) makes it unlawful to sell, install or replace any item of vehicle equipment that does not comply with the Vehicle Code or Department regulations, with a civil penalty of up to $100 for each violation and a $10,000 ceiling for a related series, and § 4107(b)(1) reaches anyone who willfully renders required equipment inoperative.

The bite most owners feel is the yearly sticker. § 4702(a), and 67 Pa. 80(a)(9) lists the lamp faults that force a rejection, including auxiliary equipment placed on, in or in front of a lamp and auxiliary driving lamps that operate with the low beams or alone. § 4703(h)(1), with a fine of up to $25 for a passenger car and $100 to $500 plus an out-of-service order for a motor carrier vehicle, bus or school bus.