Hot diggity...this sounds like a plan...makes sense to me!!! I will let
you know what I find. THANK YOU VERY MUCH!!!!!!!!!
Becky
wanting a little flash....
DANMAS@aol.com wrote:
>
> In a message dated 98-07-05 22:30:43 EDT, bmahoney@home.com writes:
>
> > when I first got the car the
> > turn signals wouldn't work unless you turned the hazards either off or
> > on, I can't remember which. Now, the turn signals do not work at all.
> > When I first hooked them up the left one would flash quickly and the
> > right one wouldn't work at all.
>
> Becky, In order for the turn signals to work, the hazard switch must be
> installed, and in the off position. Power for the turn signals passes through
> the hazard switch. When the hazard switch is on, power is cut to the turn
> signals to prevent the hazard flasher from back feeding through the turn
> signal switch, if it should happen to be left on, and powering every thing
> that is powered when the key switch is on. Other wise, your radio, heater fan,
> wipers, etc - any thing you left on when you turned the key off - will turn on
> and off with the hazard flasher.
>
> Do your lights come on and burn steady, or not come on at all?
>
> If they come on and burn steady, but don't flash, you either have a bad
> flasher or some bad connections in the circuit. Most likely, you either have
> bad ground connections, or the hazard switch is faulty (the internal
> connections are bad). Check and clean all your grounds for the turn signal
> bulbs. If that doesn't fix the problem, locate the fuse in the fuse box that
> has white wires on one side and green wires on the other. Place a temporary
> jumper from the green wire side of this fuse to the green wire on the TS
> flasher ( the TS flasher will have a green wire on one terminal and a light
> green/brown wire on the other; the hazard flasher will have a brown wire on
> one terminal, and a light green/brown wire on the other). If the lights now
> flash (with the both the ignition switch and the TS switch on), you have a
> problem in the power feed circuit to the flasher. If not, you have a bad
> flasher or bad connections in the TS switch and associated wiring.
>
> To see if it is the flasher or the connections, connect another TS bulb to one
> of the existing bulbs (one side to the green/white (RH) or green/red (LH) wire
> and the other to ground, and try the turn signals again for that side. If they
> now flash, your flasher is good, but you have some bad connections. You will
> have to trace the wires by hand, checking and cleaning connections as you go,
> from the flasher, through the TS switch, to the bulbs, and to ground. If they
> don't flash, the flasher is bad (of course, it is possible to have both
> problems at the same time - bad flasher AND bad connections).
>
> If it is a problem with the power feed circuit to the flasher, go to the
> hazard switch and remove the two green wires. Temporarly connect them
> together. If the flashers now work, the hazard switch is bad, and needs to be
> taken apart and cleaned. If they don't work, you will have to trace the green
> wires from the turn signal flasher back to the fuse box, looking for bad
> connections.
>
> If the lights don't come on at all, you have some bad or missing connections
> in the circuitry, and you will have to trace out the wiring to find and fix
> these connections. Follow the same procedure as above to help you find the bad
> connectons.
>
> To help you make sense of all this, I have added a little theory below, a
> repost of some comments I made to the Triumph list awhile back.
> ********************************
> Can anyone enlighten me as to the function of a flasher module?
>
> Peter,
>
> Perhaps I can. You are right, the hazard flasher is different from the turn
> signal flasher, although they both operate on the same principle. Each has a
> heat element and a bimetal strip. Current through the heat element elevates
> the temperature of the bimetal strip, causing it to bend. On one end of the
> strip is a set of contacts. When the strip bends, these contacts either open
> (turn signal flasher) or close (hazard flasher). The current that flows
> through the heat element also flows through the light bulbs.
>
> Functionally, the differences between the two types is this:
>
> 1) A hazard flasher will flash at the same rate regardless of the load, as
> long as the load doesn't exceed the flasher capacity. One 2 watt bulb will
> cause the flasher to operate at the same rate as four 21 watt bulbs. The
> flash rate of a turn signal flasher will vary, depending on the load. The
> current through one 21 watt bulb is not enough to cause the flasher to work
> (the lights will stay on), and four 21 watt bulbs will cause the flasher to
> operate at a high rate (till the flasher burns up).
>
> There is an excellent reason for this difference, and it is not unique to
> Lucas -- all manufacturers do this. The reason is one of safety. If you turn
> on your turn signal flashers and one bulb is out, the flasher won't work,
> giving you notification that something needs to be fixed. OTOH, when you need
> to use your hazard flasher, you need to use whatever bulbs you have. If one
> is out, you still want to be able to use the other three. You won't have any
> indication that a bulb is out, but the next time you use the turn signals, you
> will.
>
> 2) The flash sequence of a hazard flasher starts with an OFF, i.e.,
> OFF--ON--OFF--ON. The flash sequence of a turn signal flasher starts with an
> ON, i.e., ON--OFF--ON--OFF. This difference in sequence was not a design
> goal, it just worked out that way.
>
> Electrically, the differences are this:
>
> 1) The resistance of the heat element in a hazard flasher is very large
> compared to the resistance of a light bulb. To the heat element, the light
> bulb looks like a short to ground. If one bulb looks like a short, placing
> three more in parallel doesn't really matter: a short is a short! When the
> heat element raises the temperature of the bimetal strip, the strip bends and
> the contacts close. The contacts are wired such that they short circuit the
> heat element when they close. When the heat element is shorted, all current
> flows through the switch contacts and none through the heat element. As a
> result, the element cools off and the contacts reopen. Current again flows
> through the element, and the cycle starts anew. The current that flows
> through the heat element also flows through the bulbs, but because of the high
> resistance of the element, the current is much less when the contacts are open
> than when the contacts are closed -- not enough to light the bulbs.
>
> 2) The resistance of the heat element in a turn signal flasher is sized very
> carefully to the specified bulb wattage for that particular car. If the
> correct bulbs are used, the current through the element is exactly the right
> amount to cause the bimetal strip to bend at just the right rate for the
> flasher. Lower wattage causes the strip to bend too slow, and higher wattage
> bulbs cause the strip to bend too fast. Just as in the hazard flasher, the
> current through the heat element is the same current as through the bulbs.
> The resistance of the element is so low that it offers minimumal additional
> resistance over that provided from the bulbs -- the bulbs light almost as
> bright as if the element were not there. The strip contacts are wired in
> series with the bulbs. When the strip bends, the contacts on the strip open,
> cutting off current flow to the bulbs.
>
> Because the operation of the flashers is dependent on the current flow through
> them, any change in the voltage applied will also have an effect on the flash
> rate. An increase in voltage will cause a corresponding increase in the
> current, which will cause a corresponding increase in the flash rate. A
> decrease in voltage will have the opposite effect.
>
> Circuit resistance also has an effect on the flasher rate. More resistance
> reduces the current flow, and less resistance increases it. Barring a short
> circuit, the only way to reduce resistance in the circuit it to replace the
> normal bulbs with bulbs of a higher wattage rating. Higher wattage bulbs draw
> more current than lower wattage bulbs. This is one way of solving a slow turn
> sinal flash rate problem -- replace the 21 watt bulbs installed by the factory
> in most British cars with 27 watt bulbs used in most american car, bulb #
> 1157.
>
> Increased resistance is the most common problem, leading to a slow flash rate,
> or to not flashing at all. Typically, this is caused by bad connections,
> either in the circuit wiring, internal switch contacts -- particularly the
> hazard switch, or in the ground connections at the bulbs.
>
> As for testing them, I know of no way other than hooking them up to an
> appropriate load. For the hazard flasher, any bulb will do, but for the turn
> signal flasher, the load must consist of the correct number of bulbs of the
> correct wattage. In my shop, I keep a pair of bulbs handy for this purpose.
> I have soldered wire leads to them, and wired them in parallel.
> ******************************
> I think I've covered everything, and I hope it is of some help.
>
> Dan Masters,
> Alcoa, TN
>
> '71 TR6---------3000mile/year driver, fully restored
> '71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
> http://www.sky.net/~boballen/mg/Masters/
> '74 MGBGT---3000mile/year driver, original condition - slated for a V8 soon
> '68 MGBGT---organ donor for the '74
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