alrighty...if you want to get technical/written about it....we'll take the time to disect this.
This part is most applicable to your question in the code that you provided. Reading just this part of the code would indicate that there are no provisions as to the color of the bulbs in turn indicators.f) Illumination except headlamps, fog lamps and auxiliary driving lamps. A vehicle specified under this subchapter shall be equipped with parking lamps, stop lamps, tail lamps, turn signal lamps and hazard warning lamps designed for that specific function, which under normal atmospheric conditions shall be capable of being seen and distinguished during nighttime operation at a distance of 500 feet. See 75 Pa.C.S. § 4303(b)—(d).
(1) Stop lamps, turn signals and hazard warning lamps shall be visible at distance of 100 feet during normal sunlight.
However you fail to note a key passage before this one (175.66(b)):
From Chapter 153:(b) Lighting standards. A lamp shall comply with vehicle lighting equipment requirements of this title. See Tables II—IV; Chapter 153 and 75 Pa.C.S. § 4301.
§ 153.1. Purpose and scope.
This chapter specifies requirements for original and replacement lamps, reflective devices and associated equipment necessary for signaling and for the safe operation of motor vehicles during darkness and other conditions of reduced visibility.I think that about settles it....sorry.TABLE IV—LOCATION OF REQUIRED EQUIPMENT—Continued.
ALL PASSENGER CARS AND MOTORCYCLES, AND MULTIPURPOSE PASSENGER VEHICLES, TRUCKS,
TRAILERS AND BUSES OF LESS THAN 80 INCHES OVERALL WIDTH
Turn signal lamps - Location on Passenger cars, multipurpose passenger vehicles, trucks, trailers and buses -
At or near the front—1 amber on
each side of the vertical centerline,
at the same height, and as far apart
On the rear—1 red or amber on each
side of the vertical centerline, at the
same height, and as far apart as