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Indicators
philw - 23/7/09 at 10:43 AM

The rear indicator bulbs on my car are normal 21w however the fronts are 5w so they flash too quickly, what size resistors do i need and do i wire it inline on the + side of the bulb?

Guinness - 23/7/09 at 10:51 AM

Can you get 23w bulbs for your indicators?

I bought a load from Premier Wiring, 23w orange:-

Link to their ebay shop

I've got a spare pair if you want to try them?

Mike

MautoK - 23/7/09 at 12:22 PM

quote:
Originally posted by Guinness
Can you get 23w bulbs for your indicators?

I bought a load from Premier Wiring, 23w orange:-

Link to their ebay shop

I've got a spare pair if you want to try them?

Mike


A 21W bulb draws 1.75A; 5W draws about 1/2 A. So you need an extra 1.25A which a 10 ohm resistor would draw.
Fix it in parallel with the bulb. It needs to be 20W rated for safety although 10W would probably be OK when you consider the duty cycle; also depends how it's mounted to dissipate the heat.
...or just fit 21W bulbs
HTH
John.

David Jenkins - 23/7/09 at 12:39 PM

Or, if you've got bike indicators that won't take the standard car 21W bulbs, go to a bike shop and get 23W bulbs that do (usually) fit.