spontaneous high-beam, on an '89

Archives of Posts to the NZ MX5 List back in 2005
Locked
simple
Why yes, actually I do run this site.
Why yes, actually I do run this site.
Posts: 129
Joined: Mon May 01, 2006 5:19 pm

spontaneous high-beam, on an '89

Post by simple » Fri Nov 18, 2005 11:19 am

Having just written about repairing my ignition switch, I thought I
might as well blather about my high-beam switch...

My head-lamps have started switching to high-beam of their own accord
(when they were already on low-beam). It happens sometimes with
bumps, or with use of the indicators. The little blue light in the
dash comes on (as expected, from looking at the wiring diagram).

Manually switching between high/low beams usually brings it back to
OK, so I'm assuming it's either a fault in the switch, or in the
vicinity of the switch.

I've not yet had an opportunity to observe the headlamps while it is
happening, but I suspect that the fault (wherever it is) is actually
a short between the high and low-beam circuits (rather than switching
from one to the other). I expect to see that both high & low are on
at the same time - I'll check this out on the weekend.

Has anyone else seen this problem?

Has anyone here tried removing the headlamp/indicator switch and
servicing it? From looking at my Haynes manual, it appears that they
call it the "combination switch", and I will need to remove the
steering wheel first (but the pics are of the bent-stalk variety, so
may be slightly different).

Is steering wheel removal/reinstallation likely to cause me any
grief? I have access to a good selection of tools, but not a
steering wheel puller (got pulley-pullers though, so one of them
might fit).


Karl.

Josh Woof

spontaneous high-beam, on an '89

Post by Josh Woof » Fri Nov 18, 2005 12:34 pm

Yea i use to have this problem when indidcating it happened after we put the
alarm in i fiddle around with the stalk a bit and it has seemed to have
fixed it but i still don't know what the problem was ?!!!?? but greasing the
end of the indicator stick worked


[...]

From supasparky@yahoo.co.uk Fri Apr 27 17:21:43 2007
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.co.uk;
h=Message-ID:Received:Date:From:Subject:To:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding;
b=DQ4Za5DBK86XB7IFwo/q3lo/dQ6zJfbG4U60XTivGOVgBitXLLgDTBxRC5Cy2Ftlxx5eOITXidt3H2fKGox0Yo4NsvXvwA0XCaF5afIad5t/iYhdEP06p2LkRgw3vRLWkIeh54se6sVe5pUsGgOFt7tf+yMnJVUgJFNaJ5EeQxI=
;
Date: Fri, 18 Nov 2005 02:01:59 +0000 (GMT)
From: glenn roberts <supasparky@yahoo.co.uk>
Subject: RE: spontaneous high-beam, on an '89
To: MX5List <mx5list@mx5club.org.nz>
In-Reply-To: <BAY18-F95AD11DDAAB22F30533EA8D5F0@phx.gbl>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 7bit
Precedence: list
Message-ID: <aSQ1iC.A.8IE.GxYMGB@L733>

Theres a plastic "spring" in the indicator assembly
which springs the stalk back to the normal position
when you pull back and flash the high beams. I find
that in the summer it gets hot and looses its tension
and lets the stalk go into "flash" mode..very
annoying.
My car actually does it when parked in the sun and the
only reason i noticed it was that i have the flash to
pass diode installed, so my lights pop up when this
happens, otherwise id never have known, as the popups
dont come up usually in flash mode.
The spring is sort of a circle shape which is
squeezed oval when flash is operated. i guess that
putting a little bit of plastic in there to retension
it might work.

if youre battery keeps going flat in the summer theres
a pretty good chnce that your lights are coming on
when parked due to this fault.

Glenn "SLYDIT"
http://miata.cardomain.com/id/supasparky
Currently building a DIY Turbo..Subaru VF10 Turbo, Weld el manifold, 2.5"exhaust,subaru BOV, Isuzu intercooler, 330cc GTX injectors, dual feed fuel rail,RX7 air flow meter, Greddy Emanage piggy back computor.Custom full length cold air box...YEEEEEHHHAAA
Hopefully finished by summer:)

simple
Why yes, actually I do run this site.
Why yes, actually I do run this site.
Posts: 129
Joined: Mon May 01, 2006 5:19 pm

spontaneous high-beam, on an '89

Post by simple » Thu Nov 24, 2005 11:00 am

Thanks to info from Glenn, I have confirmed that I have a heat-
related failure in my headlight switch, causing high-beam to come on
when it shouldn't.

Glenn said:
Theres a plastic "spring" in the indicator assembly
which springs the stalk back to the normal position
when you pull back and flash the high beams. I find
that in the summer it gets hot and looses its tension
and lets the stalk go into "flash" mode..very
annoying.
I did some testing on the weekend, with multimeter & my mother's
hairdryer - the fault on my car is definitely in the switch, and
definitely heat-related. When it fails, both high & low beams are on
at the same time - they're shorted together in the switch.

Warming the switch with the hairdryer (with the covers removed from
the steering column) consistently prompts the failure, and cooling it
down again (with the hairdryer set to cold) makes things happy again.

It doesn't take much warmth for the failure to happen, but I suspect
that it won't happen at night if I have the heater off (and this has
proved true so far, in a few days of testing).

My car actually does it when parked in the sun and the
only reason i noticed it was that i have the flash to
pass diode installed, so my lights pop up when this
happens, otherwise id never have known, as the popups
dont come up usually in flash mode.
Whilst I don't have the pop-up mod, so it's not so easy to observe,
heating the switch into failure mode will *not* cause the headlamps
on my car to come on if the twist part of the switch is in the off
position. Pulling back on the stalk to do a high-beam flash
(regardless of twist position) does turn on the headlamp, but I can't
get this to happen just by heating the switch.

It may happen that this will be a problem if the switch deteriorates
further in some way. Secondary supporting evidence, for the
headlamps not coming on by themselves, is that the car spends its
days in full sun (weather permitting) and has not yet suffered
unexplained battery discharge. I carry jumper leads for when/if this
happens. Furthermore, my alarm is wired to complain if headlamps are
on or if they come on while alarm is set (this is to reduce risk of
me leaving park lights on accidentally).


I tried to remove the switch to examine it more closely, but I
couldn't get the steering wheel off - it is wedged too tightly on the
spline. It tried a pulley remover, but that just bent the boss (I
bent it back again OK). I'll probably have another go, applying
tension to the wheel and giving the spline a whack to jolt things.

Does anyone out there (in Auckland) have a steering wheel puller
which I could use instead? I suspect it could be done in situ,
without me needing to take the puller away with me, just as long as I
don't re-tighten the wheel excessively before driving home :-)
I'm assuming that a steering wheel puller is designed to apply force
more evenly than a basic pulley-remover.


Karl.

Locked

Return to “2005”

Who is online

Users browsing this forum: No registered users and 16 guests