RE: H4 Euro wiring

["Matt Rooke" <mrooke@fcpa.fujitsu.com>]

>Methinks my H4 bulbs are dead cause a resistance check shows zip (zero)
>(short)... :(
>
>Could someone tell me which of the three male quick connects on the back
>of these bulbs are high/low/gnd?

Careful- bulbs _almost_ never fail shorted.  Resistance is very low.
Example- 60W hi-beam filament is 2.4 ohms (P=VI, I=V/R -> R=VV/P =144/60)

You should be able to use resistance differences to identify which terminal
does what (BTDT).  Highest resistance pair = low-to-high terminals, the
remaining one is ground.  Next, the high beam filament is slightly lower
resistance than the low beam (higher power = lower resistance).

HTH,

Matt Rooke
'91cq, 80/100 H4's (w/relays)