Basic 2 and 3 way Wiring Info

Basic Wiring Info
by Reese Products

2 Wire System
Are vehicles that have the turn signal and brake lights operating on the same bulb and wire.
Up to 7.5 amps per circuit (per SAE specifications).
It will have an electrical code of "A" in the paper catalog.
3 Wire System
Are vehicles that have the turn signal and brake light use different bulbs and wires.
Up to 4 amps per circuit (per SAE specifications).
It will have an electrical code of "B" in the paper catalog.
Estimating Trailer Amperage Per Circuit:

Stop-Turn Lights 2 Amps each
Taillights 1 Amp each
Clearance and Marker Lights 1/2 Amp each
NOTE: For estimating use only. Amperage is rounded to the nearest whole value and may not apply in all cases.