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7 Amp Currnt Draw - Short Circuit Somewhere?

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Old 07-20-14, 12:15 AM   #16
Yamae
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Is there a fuse for the alternator? It is unlikely but how about line into the fuse box, both under the dashboard or under the hood?
Yes, there is. It is a big one located in the fuse box behind the battery closer to the engine side. It is indicated "ALT".

Last edited by Yamae; 07-20-14 at 06:59 AM.
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Old 07-20-14, 12:59 PM   #17
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Default Found Fusible Link(s)

Here is the update.

In the Fusible Link Block there are 4 fusible links as follows:
#1 FL MAIN
#2 FL ALT
#3 FL AM1
#3 FL AM2

I was able to identify the current loss between fusible link #2(ALT) and #3(AM1). When FL#2 is removed, the there is no current loss. When FL#3 is removed, there also is no current loss.

Looking at the Fusible Link Block after opening locking lug, it seems that on one side (fender side) #2, #3 & #4 are making contacts via a steel plate. The other side of the block (engine side) #1 & #2 are making contact with a plate. Donít know what that means.

Removing #1 FL, current loss occurs.
Removing #4 FL, current loss occurs.

Removing #2 FL, no (minimal) current loss.
Removing #3 FL, no (minimal) current loss.

Looking at repair manual, it is indicated as follows:
FL#2 ALT: Fog Light System, Door Lock Control System, Taillight System, Power Window System, Stop Light System, Power Seat System, Turn Signal Light System, Audio System, Defogger System, Motor Antenna, Seat Heater System, Cigarette Lighter, A/C System, Combination Meter, Heater System, Wiper and Washer, Power Shoulder Belt System.
FL#3 AM1: Turn Signal Light System, A/C System, Door Lock Control System, Heater System, Power Window System, Power Tilt and Telescopic, Power Seat System, Cigarette Lighter, Audio System, Combination Meter, Motor Antenna, ABS System, Wiper and Washer, Air Suspension System, Power Shoulder Belt Anchorage System.

Why is EVERYTHING on those two fusible links and those two FL seems to have many electric system duplicated.

What now? Any advise on what I should do next?
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Old 07-20-14, 01:31 PM   #18
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Is there any aftermarket equipment spliced into any part of the car electrical system? The approximate draw is in the 80 watt range at 7 amps. My thought is to check the bulb sockets. With the car in a dark garage, anything glowing? Similar can be done by using an IR thermometer to scan areas of the car for temperature fluctuations. As you said, the constant draw is going to generate heat.
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Old 07-20-14, 08:15 PM   #19
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Originally Posted by Michael View Post
Here is the update.

In the Fusible Link Block there are 4 fusible links as follows:
#1 FL MAIN
#2 FL ALT
#3 FL AM1
#3 FL AM2

I was able to identify the current loss between fusible link #2(ALT) and #3(AM1). When FL#2 is removed, the there is no current loss. When FL#3 is removed, there also is no current loss.

Looking at the Fusible Link Block after opening locking lug, it seems that on one side (fender side) #2, #3 & #4 are making contacts via a steel plate. The other side of the block (engine side) #1 & #2 are making contact with a plate. Don’t know what that means.

Removing #1 FL, current loss occurs.
Removing #4 FL, current loss occurs.

Removing #2 FL, no (minimal) current loss.
Removing #3 FL, no (minimal) current loss.

Looking at repair manual, it is indicated as follows:
FL#2 ALT: Fog Light System, Door Lock Control System, Taillight System, Power Window System, Stop Light System, Power Seat System, Turn Signal Light System, Audio System, Defogger System, Motor Antenna, Seat Heater System, Cigarette Lighter, A/C System, Combination Meter, Heater System, Wiper and Washer, Power Shoulder Belt System.

FL#3 AM1: Turn Signal Light System, A/C System, Door Lock Control System, Heater System, Power Window System, Power Tilt and Telescopic, Power Seat System, Cigarette Lighter, Audio System, Combination Meter, Motor Antenna, ABS System, Wiper and Washer, Air Suspension System, Power Shoulder Belt Anchorage System.

Why is EVERYTHING on those two fusible links and those two FL seems to have many electric system duplicated.

What now? Any advise on what I should do next?
So this is a boolean problem
You need to see which systems are repeated in both 2 and 3 (like signal lights for instance), and then check those. Since you can stop the current draw by removing either of the two, that means that the system that is drawing current is in both of those.

Or at least, I would start from that. Things that I would start from:

- Power antenna (what if it is trying to retract the antenna, and never stops?)
- signal lights (some funky stuff going on with the bulb?)
- Stop lights (Something going wrong with the third stop light, due to constant exposure to Sun?)
- Door locks (Those switches go bad all the time!)
- Or anything else that is not performing well - seat memory, steering wheel tilt, cigarette lighter, etc.
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Old 07-20-14, 08:42 PM   #20
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Removing #1 FL, current loss occurs.
Removing #4 FL, current loss occurs.

What now? Any advise on what I should do next?
Those 2 conditions mean that the IC regulator in the alternator is driving the rotator coil without the proper control. The IC regulator is connected to AM2 line and the rotator coil is connected to ALT line even when the ignition key is removed. I assume the IC regulator has lost the inhibit control or the ignition circuit has some problem.

Touch the alternator when the engine is completely cooled down and you can confirm it feeling how warm the alternator body is.

The 7A draw is also the same with the maximum current which is limited by the resistance of the rotator coil.
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Old 07-20-14, 11:12 PM   #21
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Those 2 conditions mean that the IC regulator in the alternator is driving the rotator coil without the proper control. The IC regulator is connected to AM2 line and the rotator coil is connected to ALT line even when the ignition key is removed. I assume the IC regulator has lost the inhibit control or the ignition circuit has some problem.

Touch the alternator when the engine is completely cooled down and you can confirm it feeling how warm the alternator body is.

The 7A draw is also the same with the maximum current which is limited by the resistance of the rotator coil.
Yamae, if you are suspecting alternator unit being the villain, instead of checking the current loss by a temperature, how about if I disconnect all connectors from the alternator to see if current drain stops?

Unlike other alternators I've seen, LS alternator has two connections. One is described in the service manual as "Generator Wire" and the other is labeled as "Generator Connector". I have already disconnected the "Generator Wire" to see if the current drain will stop and it did not. I will try to disconnect the "Generator Connector" and see if current drain stops. If the test stops the current drain then the problem is on the alternator and I will have to drop the alternator for repair.

I will report back.
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Old 07-21-14, 09:57 AM   #22
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Default Still Loosing Current

I have electrically isolated the alternator by disconnecting both the "Generator Wire" and the "Generator Connector" from the alternator and was unable to stop the current loss. It is NOT the alternator that is causing the current loss.

Should I go through each system in the list to see if there is any abnormality in function, as peterls have suggested? Or may be I can give the current to the system and look for a glow-in-the-dark area as RA40 has suggested. I am open for suggestions on how to approach this problem. Again, any help/suggestion would be appreciated.
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Old 07-21-14, 11:50 AM   #23
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I assume the IC regulator has lost the inhibit control or the ignition circuit has some problem.
Yamae has narrowed the area down, check that ignition circuit. I would suspect that these are modular so a swap is possible.

If that isn't it, pick-up an non contact IR thermometer. The cheap import tool paces sell them for sub $30. These are useful for finding temp variations and will help you track down any component/s that are receiving juice and generating heat. Once you find what is receiving current, you can then pick through the circuit. For something like this, you don't have to unplug a bunch of stuff which makes it easy to scan over the individual components for temperature inconsistencies.
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Old 07-21-14, 01:33 PM   #24
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... I would always suspect what I've done to the car when electrical problem like this this occurs.
Probably right. What would those areas be?

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Originally Posted by Michael View Post
I have electrically isolated the alternator by disconnecting both the "Generator Wire" and the "Generator Connector" from the alternator and was unable to stop the current loss. It is NOT the alternator that is causing the current loss.
Looking at the circuit, Yamae's diagnosis seems to make sense. Since the fault still appears when the alternator is isolated, could there be a problem with the connector plug to the alternator (e.g., a partial short between two connectors within the plug)? Actually, this is not likely - a fault like this would not be likely to have a consistent 6.8A draw; but looking for it may lead you in the right direction.

In general, you're talking about 80W of power dissipation. An IR detector like RA40 suggested should work, but to find 80 Watts (think about the heat given off by an old 100W incandescent bulb) you probably have a good chance of doing it by feel. Park in the garage, pull all FLs and fuses that you can so that you still have the 7A drain (to simplify things), and let things cool down for several hours, then start feeling around for heat. Start looking for things in the areas of your modifications (radio?).

Also, physics don't lie. If you were to very carefully follow the circuit diagram, carefully isolating segments of the circuit and considering what failures could have occurred, you will find the fault that way. If you think you've already done that and have found something that does not make sense (as you have described), it is probably because the tests were not proper - possibly due to undocumented modifications to the circuits, but maybe the tests could be re-done more carefully. If it were me, I would be out there with the circuit diagram in hand, going through things and thinking at each step what could be wrong, and what could be causing the test to be invalid. I'm not saying it should be easy to do this, just that in the end things are deterministic - they don't "just happen."
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Old 07-22-14, 11:09 AM   #25
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Default Location of Ignition Circuit

Quote:
Originally Posted by RA40 View Post
Yamae has narrowed the area down, check that ignition circuit. I would suspect that these are modular so a swap is possible.

If that isn't it, pick-up an non contact IR thermometer. The cheap import tool paces sell them for sub $30. These are useful for finding temp variations and will help you track down any component/s that are receiving juice and generating heat. Once you find what is receiving current, you can then pick through the circuit. For something like this, you don't have to unplug a bunch of stuff which makes it easy to scan over the individual components for temperature inconsistencies.
Where is the replaceable ignition circuit?

Last edited by Michael; 07-22-14 at 11:16 AM.
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Old 07-22-14, 11:16 AM   #26
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Default Finding Current Loss Area

Thank you for your suggestions.

I can check for the heat source, but this is a long shot. There are too many possibilities where a heat could be appearing. It could be a device or even a harness. It could be under the hood, or it could be under the seat. Most of things are all hidden.

If it takes heat detection to find the short, I would like to identify specific areas where I would go to check instead of blindly checking the whole car.

I would trace it from what I have done this year.

Most recently on 7/7, before the power loss happened, I took the driver side shoulder belt off from the side column because I had to take the top driver side pillar garnish of then had opened up the head liner to check for moonroof leak at the front driver side. This may be the most likely area I could check because the current loos started to happened after this event, I think. Just yesterday, I have remove the shoulder belt off again and took the pillar garnish off to see if anything could cause the short, there are none that I can see.

Then, I donít think these are causing the short because after these were done, I had no problem with battery.

6/26, I tried to shut the brake warning light off by shorting the brake wear warning switch at both front-right and rear right brake area.

4/25, Alternator rebuilt (cleaning inside then replaced brushes)
4/22, Clean the PS Solenoids filter
4/6, Rebuilt PS bump (replaced all o-rings and bearing)
2/14, door ajar switch lubed with graphite powder
2/14, All interior bulb have been replaced with LED bulbs
1/9, rear cigarette lighter fix
12/14, Dashboard Capacitors replaced (3 capacitors)
12/7, ECU Capacitors replaced (6 capacitors)
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Old 08-05-14, 10:15 PM   #27
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I've been on vacation for two weeks. During the time, I could not help thinking about the problem....

After I came back from the break, I consulted my brother for an advice. With the Repair Manual in hand, looking through the BODY ELECTRIC SYSTEM. And knowing that both FL ALT and FL AM1 are villains.

He has looked at the WIRING DIAGRAM and said it has to be either CB DOOR (30A) fuse or CB POWER (30A) fuse since others are switched by ignition key switch. Those two are among fuses under the dash and found that removing CB DOOR fuse stops the current loss.

This narrows down to followings according to the service manual:
- Door Lock Control System
- Fuel Lid Opener System
- Power Seat System.

Now my next questions are:
- What are these systems referring to, exactly?
- How do I isolate each system to determine exactly where the problem might be?

Any input again would be appreciated.
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Old 12-09-14, 04:47 AM   #28
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Default I have same issue w 97 LS

Mine reads 3.5A and kills the battery over the period of a day or two.

Mike...your troubleshooting was pretty much exactly what I did, did you ever come up with a solution?

Jim
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Old 12-09-14, 09:04 AM   #29
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Couple people contacted me with the problem of losing current as a result draining battery overnight.

I have patched up this problem as the problem is narrowed down to Junction Block No 1 (under the dashboard), Circuit Breaker ďCĒ (Door) is causing the short. When I remove the circuit breaker, the current loss stops. And I do not have, power lock, power seat, power trunk release and fuel lid release function.

I went around this by installing switch on circuit breaker as shown on the picture. One on the left is the circuit breaker and the left is the switch installed on a circuit breaker.

I use the car with out few power functions. Whenever I need those power functions, I put the switch on. I would have to look into this further when I have time to identify among the listed power functions above. But for now, it is a good workaround.
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Old 12-09-14, 01:28 PM   #30
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So likely a switch is stuck on? Electrical problems can cause fires in any make and model of cars. Especially if that alternator has a problem, it has constant power ig switch on or off.
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