Earth Problem --- I suspect:

PostPost by: stuartgb100 » Tue Aug 15, 2006 6:41 pm

Operated on their own, all electrical circuits work perfectly (well, most do, to be honest). However, if I put the dip headlights on and press down the brake lights at the same time, then try the indicators ...... well, I get different results:

seems always the n/s indicators work, but the o/s sometimes flash once then stop, sometimes they continue to flash, but more slowly than the n/s.

This is with an alternator, and the car is ticking over.

The o/s wing indicator is always noticeably dimmer.

However, if I operate the indicators on their own (with the engine running)
then the the o/s indicators work fine, and much faster.

Without the engine running, the o/s just flash once and then stay on.

Can anyone deduce where the problem might be found?

Regards,
Stuart.
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PostPost by: types26/36 » Tue Aug 15, 2006 6:53 pm

Stuart,
At the same time you are checking the earths/contacts check that the bulbs (left & right) have the same wattage including the side markers.
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PostPost by: stuartgb100 » Tue Aug 15, 2006 7:41 pm

Brian, thanks.

Good point, that I might have inherited different bulbs from PO.
Will double check.

However, when operated on their own the wing flashers are of similar/equal brightness.

Regards,
Stuart.
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PostPost by: john.p.clegg » Wed Aug 16, 2006 5:57 am

Just an educated guess but the first port of call is the o/s indicator earth,try running a length of wire tied down to a good earth and poking around with it while the fault is there....

If that fails the problem is a high resistance connector in the feed path to same.the best way of finding this is to run a temporary live wire (tied down to a known good 12v supply and this time work from the indicator back to the switch again while the fault is present..

Disclaimer:- You should have some electrical knowledge to perform this(best done with a sharp pin on the end of the wander lead to pierce the insulation)

I will not be held responsible for electrical fires...

Best of luck...

John :wink:
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PostPost by: hatman » Wed Aug 16, 2006 8:24 am

Despite the fact that you've got an alternator (what output, by the way?) your symptoms do sound to be those of a general lack of electrickery in the system. How good/old is your battery and is the alternator really up to running everything at tickover? :)
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PostPost by: ppnelan » Wed Aug 16, 2006 8:43 am

Why not just rev the engine a bit... :)

That's what my local MoT station does when the indicators don't flash (quick enough) on the test. Mine has a dynamo.

:arrow: Matthew
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PostPost by: stuartgb100 » Wed Aug 16, 2006 4:39 pm

Thanks all for the suggestions, will follow them through. And yes, I better check the alternator output and the condition of the battery.

Not been an issue so far (engine starts first time, so the battery charge level/retention has not really been tested).

Regards,
Stuart.
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PostPost by: denicholls2 » Wed Aug 16, 2006 9:52 pm

Based on 1969 Europa experience, but I bet you have similar hardware.

The indicator flashers are current-sensitive; that is, there must be a certain amperage flowing through them or they will not blink. On my Europa, the problem you see is manifested when I install LED bulbs (to reduce the current flow in Lucas wires.) LED rears blink the indicator once, then it stops. The taillamps continue to blink normally. But if I add LED fronts, the current falls below the threshold entirely and the circult does not blink.

Although it's good to make sure you have consistent wattage drain from all bulbs, I believe your problem is likely to be one or a combination of the following, in order:

1. Your battery is getting old and is no longer as good at keeping up with periods where the idle output of the alternator/dynamo does not cover total current demand. These systems were, I believe, designed to run in temporary deficit under certain conditions (the Europa has many items which in combination will exceed the available alternator output, I believe headlamps and rad fan together are sufficient to push me negative at idle.)

2. Your alternator/dynamo is getting old and is worse at covering high current demand at idle than it once was.

Note that neither of the above issues is really a problem as long as you don't spend a lot of time driving in deficit unless you want your blinkers to work under these conditions.

3. An inadequate ground is reducing the ability of current to flow to the relevant system components.

This one's a problem because it is the breeding ground for an electrical fire. Check all of your grounds and connections regularly; a dielectric grease (like Vaseline) is great for keeping them from corroding.

One solution I have yet to follow myself is to replace the flasher relays with ones that are not current-controlled. In my case, however, alternator output has no effect on flasher behavior -- there simply is not enough current draw from the load side of the system.

-- Doug Nicholls, 54/1822 Ma~
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PostPost by: ianf » Tue Sep 05, 2006 9:00 pm

Stuart,

I had a similar problem when I bought my car. I changed the flasher unit and they stopped working altogether. After a couple of years revving the engine at MOT time a local Lotus bod suggested fitting a solid state flasher unit from I believe a late RWD Escort (I would have to have a look at mine to give more details as I changed it 7 years ago). This completely fixed the problem.

I think I discovered the root of the problem recently. A little while ago a repeater bulb blew and I trotted off to Halfors for a replacement. I could only get a 5W bulb the manual suggests it was originally 3W. The blown one was 5W - maybe the change of bulb spec was too much for the bi-metallic unit?

Hope this helps.

Ian
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PostPost by: wojeepster » Tue Sep 19, 2006 12:11 am

I like the solid state flashers and have fixed sluggish or stopped ones before this way. If this does not help I suggest voltage drop testing to see where the problem lies. The beauty of this method is that you do not have to take it apart to use this method. It is fully explained in Tracy Martins How to diagnose and repair automotive electrical systems........ It is simply the best book I have ever read on automotive electrics and I a have read a bunch of them. His was the first book that really shows you how to fix it. It would be cheap at 5 times the price.
8)
http://www.amazon.com/gp/product/076032 ... 53?ie=UTF8
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