Monday, October 02, 2006

VW Type 3 Stop-, Tail- and Turn Signal Lights

One of the modifications I'm making to the car is to replace all of the red and amber lamps with LEDs. Here is a list of the bulbs and their power consumption:

Location Bulb Qty. Incandescent Power LED Power
Peak Typical Peak Typical
Headlights H4* 2 60W 55W N/A
Front Parking/Turn Signals 1157 2 21W 5W 3W 0.4W
Brake Lights 1156 2 21W 0W 3W 0W
Rear Turn SIgnals 1156 2 21W 0W 3W 0W
Tail Lights 67 2 5W 5W 1W 1W
Total Wattage: 256W 130W 140W 114W
Total Current @12V: 21A 11A 12A 10A

While all of these wattages are miniscule compared to the traction pack capacity, my DC to DC converter is only 30A. If you add in the current draw of the heater blower motor, rear defrost, seat heaters, and other lighting, you pretty quickly approach or exceed its capacity, particularly at night with the high beams and flashers going. That said, with a full complement of LED bulbs running $150 (that's with the fancy 3W Luxeon bulbs for all the 1156es and 1157s), you could also upgrade the DC to DC at that price. But with a pair of conventional bulbs approaching $5, you only need to replace them 4 or 5 times to break even on bulb cost. Plus the lag between, say, applying the brakes and having the brake lights illuminated is all but eliminated.

*I replaced the stock sealed-beam lights with a pair of 7" round Hella H4 housings.