Just a thought, maybe it senses the surge current that occurs prior to the
fillament heating and the resistance increaseing… That being the case
perhaps the ideal may be to wire a large capacitor across the light power
feed and ground to simulate the initial current surge as it charges…
Just my two cents worth
Duncan
82 XJS-----Original Message-----
From: owner-xj-s@jag-lovers.org [mailto:owner-xj-s@jag-lovers.org]On
Behalf Of Luis Gasperini
Sent: Thursday, 3 December 2009 11:49 a.m.
To: xj-s@jag-lovers.org
Subject: Re: [xj-s] change running lights to LED’s
In reply to a message from Kirbert sent Tue 1 Dec 2009:
Of course I used one such resistor per LED, and they were
similar to this one:
http://tinyurl.com/yffa27a
therefore capable of handling the power at 12V. But it did
not fool the computer, though it drew about the same amps
than the original bulb. But, (as already said), a smaller
bulb in parallel with the LED DID FOOL the computer, though
it drew less amps than the original bulb.
What I’m GUESSING is that the OBC does not check the drawn
current, but maybe the resistance of the circuit with the
lights off, which is by FAR a lower value than those 35
Ohms. You can check that, by measuring the bulb resistance
with a digital multimeter.
The original message included these comments:
35 ohms sounds about right for a running light bulb – but of course
you’d need two, or however many bulbs are in the taillights. For my
turn signal bulb, the wattage is higher so the ohmage is lower.
Either way, though, the resistor must be able to handle the wattage,
which means a little 1/2 watt resistor won’t do.
That’s pretty tricky! D’ya suppose they came up with that scheme
just to prevent the installation of LED’s?
–
Luis Gasperini / '91 V12 XJ-S conv. 5sp
Montevideo, Uruguay
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
// please trim quoted text to context only
// please trim quoted text to context only