In message <B588D5F5.F75%eyates@enteract.com>you write:
>
>Hello everyone,
>
>The dash lights dimmer on my '78 is on the fritz. Thanks in advance for any
>thoughts.
>
>Its first symptom was a reluctance to bring the dash lights up to full
>brightness. After a while they went out altogether. With the dash lights
>dead (but the headlights on), if the knob is turned up, the unit becomes
>incredibly hot, presumably because it is not passing any of the current it
>should. It stays cool if I keep it turned all the way down, as if I were
>dimming the lights completely.
The dimmer is just a hi-power variable resistor. If the traces inside
are burned, there is not much you can do but to replace it. I still have
mine in pieces, it never worked and the knob was seize and cannot be
rotated.
>My question is, what if I were to simply bypass this dimmer switch? The
>truth is, I never use it to dim the dash lights; I prefer them at maximum
>brightness all the time. Can I bypass the switch safely? How would I do
>this? I have three wires going into it. (Perhaps there should be four wires
>going into it... there are four connectors. ?)
>
Yes, you can just bypass the dimmer and get full brightness all the
time. There are three wire with .25" female connectors. The red one
is the power and the other red/white goes to the instrument lights.
You can probably get a "Y" type .25" connector with 3 male blades from
Radio shack, but I don't think they are insulated so you'll have to
use some electrical tape on it.
However, the electronic technician in me would put a fuse in between the
red and red/white wire. I counted 8 lights connected to this circuit and
if I remember correctly each bulb only take around 2-300MA. Playing save
and say 500MA per bulb that would mean a total of 4A, so a 4A fuse should
be use.
On the other hand I have made a solid state version of the dimmer. If
you are feeling adventurous here are the links to pictures and schematic
to what I've done.
http://www.ece.concordia.ca/~dave/carpics/dim1.jpg
http://www.ece.concordia.ca/~dave/carpics/dim2.jpg
http://www.ece.concordia.ca/~dave/carpics/dim.jpg
Dave |\ | | |
_______________________________________/\ /\ /\_____| \|_____| |____________
Dave Chu \/ \/ | /| | |
Dept. of Elec. & Comp. Eng. |/ | | |
Concordia University Voice:(514)848-3115 Fax:(514)848-2802
1455 de Maisonneuve W. H961 Email:dave@ece.concordia.ca
Montreal, Quebec, Canada H3G 1M8 http://www.ece.concordia.ca/~dave/addr.html
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
