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  #16  
Old 05-01-2007, 07:20 AM
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Whew, what a long post! All the better, though.

An aftermarket stereo was recently installed, but since it was installed I have not had the battery drain on me. Then again, as said before, I've been driving it almost daily since the installation. I told them to use the harness (since I had paid them previously to use the harnesses) but they disregarded my instructions and wired it in directly anyway. I was more than a little pissed off about that. I mean, that was my money they threw away. I bought the harnesses, I paid them to connect them. Bah. Serves me right I guess.

I haven't pulled their work out to inspect it, but it seems to be working. Also, the aftermarket radio has a 15A fuse in it, but I am 95% certain they didn't install a separate fuse inline before the radio. Again, haven't pulled it out to look, but it's my guess.

I had also pulled the radio fuse (for safety more than anything else) before the install had happened, since the wires were just hanging out. Sadly it did not solve the electrical problems.
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  #17  
Old 05-01-2007, 04:03 PM
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Update: After a lot of hassle, I did get the water temp sensor replaced. Considering how easily the old one fell apart, it makes sense it was throwing a code. The new one works fine; no check engine light so far.

On the other hand, I went to start the car to move it out of the way a few hours later, and got nothing from the starter. No click, nothing. Then I turned off the ignition, put my foot on the brake, and upon trying again it started right up the first time. Thinking this odd I shut the car off, took my foot off the brake, then tried to start it. It started just fine.

The heck is going on...?
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  #18  
Old 05-01-2007, 04:42 PM
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Back to square one.

As you say this has become a lengthy thread and as a result, rather confusing. I can not locate confirmation to the affect that you have properly checked for the rogue current drain which certainly MUST exist.

You must disconnect the battery earth terminal and connect a multimeter, switched to the maximum amps range, between battery negative and ground. N.B. MaKe semi permanent and reliable connections, so that faulty contact does not confuse the issue. If there is no reading, select a low milli amp range on the meter, so as to register even a very small leakage.

If you can not measure any current drain, the problem must relate to the battery. Sometimes there can be an internal fault path. Alternatively, strange as it may seem, dirt and moisture across the top of the battery can provide a fault path sufficient to discharge a battery over a period. Make sure yours is clean.

In the event that you you can measure a current drain, remove fuses one by one. If the the drain ceases, you have located the faulty circuit and thus narrowed your search. Should this prove unsuccessful, disconnect the alternator wring and again check the reading. There could be an internal diode with a reverse leak.

This will then leave only the main positive battery cable or the mechanicals of the fuse box as being leakage points, highly unlikely events. However in your case I note that things were messed about in this area, which makes one rather suspect regarding the fuse box.

These tests will cover ALL possibilities and WILL locate your problem, provided all are done properly. Most important one stage at a time. When trouble shooting, it is important not to make more than one change at a time , otherwise you lose the plot. Be methodical and careful, even to the extent of noting down each test as you make it. It is easy to forget where you are if you are interrupted. I have been there.
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Last edited by Trevor; 05-01-2007 at 04:57 PM.
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  #19  
Old 05-01-2007, 05:20 PM
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You are absolutely correct; I have not done this. Tomorrow the rain should cease and I will once again venture out with tools in hand.

Thank you as always, Trevor. Wisdom speaks true once more.
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  #20  
Old 05-02-2007, 03:11 PM
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I have just completed a full test of the electrical system. The test was performed with the car off and the doors closed (I got my little brother to assist with the kick-panel fuse box once we got to that point, so the door would remain closed and the lights off). Sadly the multimeter's internal fuse blew partway through the internal testing, so I don't have perfectly accurate results (results to the ones, not to hundreths) but they're results nonetheless. Here is what I found.

For the under-the-hood fuse box, the following circuits draw power:
(Multimeter in 40 mA range)

Clock: 10.72 mA
Hazard: 3.31 mA
SBF 5: 3.00 mA

However, as I did more testing, I found that the clock fuse only draws power when the SBF 3 fuse is in place. Removing the SBF 3 fuse also drops the current by about 10.72 mA. Test was done by removing SBF 3, then removing the clock fuse.

As for the internal fuse box, pulling the following fuses caused a ~1 mA drop on the multimeter (though I was in the 4 A range, and thus was not accurate):

-Door Lock
-EGI Unit + AT Unit

When my brother put either of these fuses back, it caused a spike in amperage which quickly returned to ~15 mA. It was more the spike which gave it away than anything else. Also, he told me that replacing the door lock fuse made a slight "click" noise. Replacing the EGI+AT fuse made no sound.

I know not the layout of the SVX electrical system. Can anyone decipher my results? Much appreciated!

And thank you, Trevor, for the detailed walkthrough. I was able to do the test right away!

Last edited by Nomake Wan; 05-02-2007 at 03:24 PM.
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  #21  
Old 05-02-2007, 04:32 PM
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Quote:
Originally Posted by Nomake Wan
I have just completed a full test of the electrical system. The test was performed with the car off and the doors closed (I got my little brother to assist with the kick-panel fuse box once we got to that point, so the door would remain closed and the lights off). Sadly the multimeter's internal fuse blew partway through the internal testing, so I don't have perfectly accurate results (results to the ones, not to hundreths) but they're results nonetheless. Here is what I found.

For the under-the-hood fuse box, the following circuits draw power:
(Multimeter in 40 mA range)

Clock: 10.72 mA
Hazard: 3.31 mA
SBF 5: 3.00 mA

However, as I did more testing, I found that the clock fuse only draws power when the SBF 3 fuse is in place. Removing the SBF 3 fuse also drops the current by about 10.72 mA. Test was done by removing SBF 3, then removing the clock fuse.

As for the internal fuse box, pulling the following fuses caused a ~1 mA drop on the multimeter (though I was in the 4 A range, and thus was not accurate):

-Door Lock
-EGI Unit + AT Unit

When my brother put either of these fuses back, it caused a spike in amperage which quickly returned to ~15 mA. It was more the spike which gave it away than anything else. Also, he told me that replacing the door lock fuse made a slight "click" noise. Replacing the EGI+AT fuse made no sound.

I know not the layout of the SVX electrical system. Can anyone decipher my results? Much appreciated!

And thank you, Trevor, for the detailed walkthrough. I was able to do the test right away!
O.K. You have demonstrated that you know what you are about. The problem is that the standing currents you have discovered are what could be as normally expected.

I now assume that the what you have detailed, is the only current drain registered at the battery connections. Therefore the alternator can be eliminated as being suspect.

You shot your meter fuse because either you put it across a voltage source, or did not first use a high current range. But not to worry as these things happen and are the exact reason for the fuse. It will likely be a quick blow low current item and should be replaced with the same. Do not shove in just anything on hand, as next time you will loose your meter.

While you are at it, purchase a couple of spare fuses and also get hold of some test leads with small alligator clips on each end, as used by experimenters. Usually available in sets at a very cheap price. These will assist you to semi permanently connect your meter. See advice which follows.

When you get a new fuse for your meter, chase up again on the door lock and EGI Unit + AT Unit circuits, which appear to be possibly suspect. Isolate the two circuits by removing the fuse for each and again check the currents.

The spike you so correctly report is not surprising as the door lock circuit involves a solenoid, which will involve a high inrush current and back EMF. The standing current is what will affect battery drain.

To safely measure the standing current, bridge the applicable fuse with your meter on a say 250 - 100 MA range, fuse link in place, so that the solenoid is energised and the inrush current has passed. Remove the fuse and take the measurement, then replace the fuse in order to prevent back EMF spike before disconnecting your meter. Do not operate any door lock switches which could break the circuit while the meter is connected and on a MA range.

Intricate and tedious I realise, but you have your little brother to assist, ( give him my compliments as he is an essential asset.) I am sure you will understand the implications of all that is involved. Consider yourself an expert and enjoy.

N. B. If the battery normally discharges over night, you could remove a particular suspect circuit fuse and see if the trouble has been eliminated. This would be simple but an excellent definitive test. If time with the car out of use is not a problem, this could be your first method of approach.

Do not despair, you are making progress in respect of a problem which taxes and sometimes defeats experts.
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Last edited by Trevor; 05-02-2007 at 04:36 PM.
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  #22  
Old 05-02-2007, 07:01 PM
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Ha ha! The very first thing I did was go out to buy alligator clip test leads--I stuck one on the negative battery harness, but used a normal test lead on the negative battery terminal (as the alligator clip was not large enough to grip the negative battery terminal).

But I didn't begin with a high current range--I began with the smallest. Small mistake; live and learn, I guess?

Sadly the meter is not professional--its ranges are 400/40 mA or 4/40 A. Rather poor, I know. However, I shall get some new fuses for it and check those two suspects tomorrow.

Yes, these drains were the only ones. As soon as Clock, Hazard and SBF 5 were removed, drain dropped to 0 on a 40 mA range.

You say these are normal... but the hazard fuse has me wondering. I notice a power drain while driving the car as soon as I turn on the turn signals...

Thank you for your help so far. I will get back to you tomorrow morning on the results of the second fuse test. Unfortunately the car doesn't discharge overnight--it discharged over a month (though I had not used the car during that month, so it could've been discharged sooner), and then lost current over a week (the week my car was in the shop getting exhaust work done).
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  #23  
Old 05-02-2007, 07:52 PM
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You are dead on track. Sorry I had forgotten about the hazard/turning light detail you had reported.

For a start change the flasher module. I am not sure if the SVX has the standard type of off the shelf component, but in any event it should not be too expensive.
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  #24  
Old 05-02-2007, 08:58 PM
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Excellent. Will do that...

...

Anyone know anything about the flasher module?
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  #25  
Old 05-03-2007, 04:27 AM
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WHOA!.....STOP.....THINK

Finally, you have done some measurements.
What do these measurements tell you?

1. Two supposedly independent circuits, fed by fuses which you call clock and SBF3 are now not independent at all.

If I guess your naming convention correctly, fuse SBF3 is supposed to feed the cigarette lighter and the rear view mirrors only. They quite obviously are linked to the clock circuit now ........ you said somebody had played fast and loose with the wiring, and this is undoubted proof that they have! This might very possibly explain why the clock fuse blew!

2. The hazard warning circuit is taking current.

Why? It should be switched off!

So is the switch defective?
Is the wiring to blame?
I dunno ........ but you've got a test meter, so you can find out where this current is going.


3. The total leakage current is 10.72 mA + 3.31 mA + 3.00 mA + 1 mA + 1 mA = 19 mA (approx).

Assuming a partially charged battery with, let us say, 30 Ampere hours worth of charge then this will give you 1578 hours (or more than nine weeks) before it goes flat.

So either your battery is not as good as you think it is, or you are leaving something switched on.

I don't suspect your flasher unit, but I do suspect the wiring or the switches. You are the man with the meter, so you can find out what it is.
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I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science, whatever the matter may be.
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  #26  
Old 05-03-2007, 06:20 AM
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Ah sorry... I had no idea what SBF3 was, so I assumed Trevor thought they were on the same circuit. Well you know what they say about people who assume things...

Yeah, I was thinking about the draw time... it made me quite curious. The battery's been checked and re-checked and I can't find anything wrong with it. It drained while the car was in my possession once. The next time, the car was out of my hands; and while I don't want to suspect Mann of doing anything that would cause the battery to drain abnormally fast, fact is he had my car for that week.

Also, I noticed while the clock fuse was blown that the interior lights switched by the door timer are also on the clock fuse circuit--as when the clock fuse blew, I lost the lights that normally turn on when I open a door. Now, is that supposed to happen, or are these supposed to be on SBF3? The lights do not come on when the doors are closed, but could something in that loop cause a short?

As you said, I have the meter... time to go check a whole bunch of other stuff. Good thing I've taken apart the dash once already.

EDIT: By the way, the names of all the fuses I listed are off of the plastic covers of their respective fuse boxes. I'm not nearly witty enough to trace circuit paths and create neat names.
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  #27  
Old 05-03-2007, 06:53 AM
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YES, all please WHOA!.....STOP.....THINK

Again the issue is being confused.

No guessing please. Fuse SBF3 is a 45 Amp main distribution fuse, as is SFB5.

SFB3 supplies numerous permanently energised fused sub circuits, including the clock and original audio. N.B. Therefore a common connection between these fuses exists as part of the original wiring.

There could be a leak via the flasher circuit, if there is a leak within the hazard switch. Removing the flasher unit will eliminate or prove this possibility.

One step at a time, otherwise you will lose your way. The clock and original audio supply circuit will be next on the list. There are also additional permanent supply circuits to be considered.

Be sure that I have personally designed and overseen the construction of electrical circuits, immensely more extensive and complicated than what we are dealing with here.

Edit P.S. I have now noted the latest message posted during my typing of this text.

Quote "Ah sorry... I had no idea what SBF3 was, so I assumed Trevor thought they were on the same circuit. Well you know what they say about people who assume things."

Read above, I did not "think". I knew and I never assume, when dealing with things technical.

I have already pointed out that the battery could be faulty. The actual current drain is in doubt, as you were not able to use the milli amp range on your meter. Therefore at this stage this contingency remains pending and subject to further confirming measurements. I do not require instruction regarding Ohms Law. Read again:-

"When you get a new fuse for your meter, chase up again on the door lock and EGI Unit + AT Unit circuits, which appear to be possibly suspect. Isolate the two circuits by removing the fuse for each and again check the currents."

I have covered all angles in detail. Too many cooks are spoiling the broth. I have not the time, patience, or inclination to solve crossword puzzles. I leave you two to it. *<)
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Last edited by Trevor; 05-03-2007 at 07:56 AM.
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  #28  
Old 05-03-2007, 08:13 AM
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Trevor is probably right about SBF3 being a 45 Amp fusible link; I apologise to both of you for muddying the waters over that point. You can now entirely discount my first conclusion.

The bald facts are however that we are both thousands of miles away from you, and cannot look over your shoulder as you do the diagnostics but you've got the meter and sufficient common sense to find the problem. You can download the wiring diagrams, and lots of other stuff, from here http://seccs.org/tech/manuals/1992_SVX/index.html
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  #29  
Old 05-03-2007, 01:18 PM
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Thank you both.

Trevor: I did use the milliamp range while testing the under-hood fuse box. In the milliamp range, I registered no load at all when clock/sbf3, hazard and sbf5 were removed. Zero. It was when I was partway through testing the interior fuse box that the internal fuse blew and I had to switch to amps.

IPR: Thanks for the link. I'll take a look and see what's up. I had the radio do some weird stuff when I went over a bump in the road today (and the trim needs to be moved anyway) so it's due to be inspected.

I've got work today, so the results of the second test may be delayed a day or two.
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  #30  
Old 05-03-2007, 06:54 PM
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batery drain.

Make sure your trunk lite sw is turning the lite off. You could just take the bulb out and see what happens in a few days?
Good Luck,
Keith
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