Headlight switch fixes (was A frightning experience(Part 1))

["Walter" <Whalt@xxxx>]

A bit of headlight switch etiquette I've learned from Rob at PJ Grady: When
pressing the button, don't stab it with one finger in the center. This will
wear away the little headlight switch symbol, and it will look even worse
while the backlight is on. Instead use two fingers to press the switch on
either side to give a balanced force so it doesn't tend to jam. The same
goes for the hazard switch.

Some helpful hints when servicing light switches:

Mount it in the dash so that the white tab faces the passenger side of the
car. The effects of gravity will help the mechanism to latch/unlatch
properly instead of working against it.

If the spade lug sockets are too tight or misaligned in the plastic holder,
they will push the lugs into the light switch body. This doesn't damage the
switch, but is still something to consider.

The switch can be replaced without removing the center console. Remove the
backlit plastic panel and pull the switch out using an IC extractor tool.
The wires are long enough to reach through the hole to do anything you need.
But first disconnect the battery!


My original headlight switch socket had a poor electrical connection.
Vibrations caused blinking lights and a potential fire hazard, and there was
nothing I could do to get the socket to seat better. I tried removing the
wires one at a time to clean and tighten each spade lug socket as you would
do with a relay socket, but I had no luck doing this without destroying the
metal. I tried picks, drill bits, paper clips, etc. Each spade lug socket
came out destroyed. I tried in vane to find replacements locally, but
nothing would fit the plastic socket properly. So I ended up not re-using
the original plastic and instead used individual ones which I crimped then
soldered and covered with heat shrink. I labeled each wire with
electrician's numbered tape bought at Home Depot and scratched corresponding
numbers on the plastic light switch body. I originally stuck the number
tape on the switch body as well, but there wasn't enough clearance to put
the switch back in the dash without the sheet metal scratching the numbers
off.

Sure, this is not an 'original' looking repair and perhaps it lowers the
value of the car, but I know the connector is not going to catch fire. I
may have been able to purchase OEM replacements from a Delorean vendor, but
I prefer to see that each connector is seated individually even though there
is now a higher risk of confusing the wires should it ever be disassembled
again.


On the subject of headlight switches, I would like to publicly apologize to
the vendors involved for saying that I was sold a used DMC headlight switch
as new. My mistake. The headlight switch was actually new, it just sat on
the shelf for so many years that it accumulated a lot of dust. Someone
wiped the dust off but left a residue under the switch cap and lip which
made it appear to have been installed in a dash at one time where air
circulating around it would deposit the characteristic dust print which I
thought I saw.

I bought my NOS headlight switch from DMC Joe who dropped shipped it through
PJ Grady who got it through DMC Houston (I think.) It's nice to see such
co-operation among so many people. Anyway, once I had a new headlight
switch in hand, I decided to do an autopsy on my old switch. I disassembled
it and found NOTHING wrong with it. I expected to see a broken mechanism or
burned contacts, but everything looked new.

The problem was that the switch wasn't latching most of the time. It uses
something like a wide staple looking wire which finds its way through a maze
as you press the button. On mine, it just didn't want to catch even though
the parts inside had no wear. It seems that it was a stroke of luck which
way the wire moved every time I pressed the button. I think it is just a
bad design from the start. Anyway, the only rhyme or reason I could come up
with for the problem was that the movement of the wire may be adversely
affected by gravity. If the switch is mounted in the dash 'upside down'
then gravity will tend to make the wire feed through the maze the wrong way
causing the switch not to latch.

Sorry to be so long winded, but I'm sure some of you will benefit from my
experiences.

Hey Mr. Flames,

Glad to hear that it didn't get any worse than it did. I hear that the
white powder is very hard to clean up. People say that the longer it stays
on, the harder it is to get off. When my headlight switch went flaky, I
jumpered it out at the relay until I got a new one installed.

Walt Tampa, FL