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Discussion Starter #1
I'm only working with a multimeter and a 40 dollar scan tool that I cant use on it without power.

The Negative Cable arcs something gnarly when attaching the neg cable with the pos cable already attached.

I just replaced the alternator and absent mindedly did not finished tightening that nut at the top that connects to a lead wire.drove it around like that for about 10 minutes during test drive, then again later. During the 2nd drive when we stopped there was a gnarly smell like clutch the bat light came on blah blah blah ended up ignoring wisdom and continuing to drive it which I am now sure has lead to some kind of electrical wire mating dance and my wife being way more than mad.

I'm trying to track it all down and square it up or at least try before paying an automotive electrician.

Do I start at the fuses and work my way from there?
should I just not bother adding current due to risk of fire and damage to system?
Should I logically assume that the issue is a High Resistance Short to Ground at the alternator and cry at the thought of having to RnR the thing yet again and how do I test to make sure?
 

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Tis what I'm thinking,do I just touch leads to the housing and that lead connector at the top of the nator and read continuity?
Not sure but if you just disconnect the alternator, you can then connect the battery and check things out. If no more issues, it is the alternator. Right?
 

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In the underhood fuse box are a couple of phillips/8mm screw heads. That is where the B+ wire from the alternator feeds into the system. You can carefully remove the screw that holds the wire from the alternator and disconnect the B+ alternator wire from the system without disconnecting the battery. Just be careful not to touch a ground with your ratchet while removing it or you'll get more sparks. Once the alternator is disconnected you can see if there is still a significant draw on the battery causing your arcing when you connect/disconnect the battery terminal.

Leaving the B+ wire loose would have caused some extra resistance, and heat, causing issues. It shouldn't have damaged the alternator unless it was too much heat and melted something on the alternator itself, not just the rubber boot. If you didn't use a Denso reman alternator there's a good chance the alternator was no good right out of the box and leaving the wire loose was just an added problem.
 

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Discussion Starter #6
In the underhood fuse box are a couple of phillips/8mm screw heads. That is where the B+ wire from the alternator feeds into the system. You can carefully remove the screw that holds the wire from the alternator and disconnect the B+ alternator wire from the system without disconnecting the battery. Just be careful not to touch a ground with your ratchet while removing it or you'll get more sparks. Once the alternator is disconnected you can see if there is still a significant draw on the battery causing your arcing when you connect/disconnect the battery terminal.

Leaving the B+ wire loose would have caused some extra resistance, and heat, causing issues. It shouldn't have damaged the alternator unless it was too much heat and melted something on the alternator itself, not just the rubber boot. If you didn't use a Denso reman alternator there's a good chance the alternator was no good right out of the box and leaving the wire loose was just an added problem.
Well it'd be nice if that's all that was wrong but even when I disconnect that wire at the 120 amp fuse, and the post at the alternator, current is drawn as soon as I attach the NEG cable, less arcing mind you, but arcing none the less. The battery discharged completely from 12.46 v to 0 in 90 seconds before I tested the voltage.

So the alternator IS probably(undoubtedly really) fried but there's other gremlins now. the 120 amp fuse upon visual inspection looked ok but would I check for resistance post to post on the fuse to make sure?

now when I had my amp clamp on the B- cable I tested from the B- to engine ground and found voltage...without the B- being attached to bat, again I'm sleep deprived, but doesn't that indicate that voltage is flowing from the positive side into the system? Or am I completing the circuit with the leads.

or am I over complicating this and there's a simple test I need to do that I'm not thinking of?
 

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Exactly where did you test and what voltage did you see? And what was disconnected? I don't really understand what you're doing. You're just not being very clear.
 

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I tested voltage at the battery between posts, I checked from posts to ground, I checked from battery negative to neg battery cable. I checked continuity and mvdc readings of the fuses. I disconnected the alternator positive cable from the alternator top post and then tried to connect negative battery clamp which then arced when contact was made at the post. I then disconnected the alternator positive cable from the fuse box and again the neg clamp arced at the post. So I disconnect the rear positive cable from the fuse box and the clamp did not arc. The fuses pass visual inspection they all have resistance, they all read 2.0-2.2 MVDC when I check the ac relays they all get roughly the same readings which I of course did not right down, that's where I have stopped testing, MY understanding at this point is something in the main fusebox (or those two other electrical boxes to the passanger side and front of car respectively which I haven't figured out what they are yet) or that cable is bad.

I've read that Honda has recommended replacing the fuse box itself which I could see being one of those 1:100 hail mary fixes but I dunno how to test any of this properly without a completed circuit to the battery. So until I figure that out I'm reaching into the dark .
 

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What is MVDC? I know what VDC is (volts direct current) but not sure what you're referring to with MVDC. Also, you need to check your terminology. Resistance is a conductors ability to "resist" current flow. If you disconnect the battery cable from the battery then the resistance between the cable and the battery is infinity or high resistance. If you connect the cable to the battery then it's low resistance between the post and the cable. A "short to ground" would be low resistance, like the battery cable connected to the battery example, so if you have something drawing current, or a short, that is extremely low resistance. When you say your fuses have resistance that doesn't make any sense as you cannot measure any resistance on a fuse by checking with an ohm meter. If there is current flow across a fuse it will have a voltage drop which can equate to some amount of resistance but I don't think you're getting that deep into the electrical theory. I'm guessing you meant your fuses have continuity, or are in tact and can conduct current.

Obviously, you have some kind of parasitic draw occurring when you connect the battery terminals. You need to determine which circuit that draw is on. If you disconnected the alternator battery wire and it's still there then it's not the alternator. The only way you're going to find this is to connect it up and find the circuit that is causing the amp draw. It would be helpful to know the amount of draw by using an amp clamp style meter. You can often use your DVOM in the amp mode in line with the battery cable but most meters have a 10A fuse that will blow if you put more than 10 amps through the meter.

You might want to do some studying and research on how to find a parasitic draw that is draining the battery.
 

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Discussion Starter #10
What is MVDC? I know what VDC is (volts direct current) but not sure what you're referring to with MVDC. Also, you need to check your terminology. Resistance is a conductors ability to "resist" current flow. If you disconnect the battery cable from the battery then the resistance between the cable and the battery is infinity or high resistance. If you connect the cable to the battery then it's low resistance between the post and the cable. A "short to ground" would be low resistance, like the battery cable connected to the battery example, so if you have something drawing current, or a short, that is extremely low resistance. When you say your fuses have resistance that doesn't make any sense as you cannot measure any resistance on a fuse by checking with an ohm meter. If there is current flow across a fuse it will have a voltage drop which can equate to some amount of resistance but I don't think you're getting that deep into the electrical theory. I'm guessing you meant your fuses have continuity, or are in tact and can conduct current.

Obviously, you have some kind of parasitic draw occurring when you connect the battery terminals. You need to determine which circuit that draw is on. If you disconnected the alternator battery wire and it's still there then it's not the alternator. The only way you're going to find this is to connect it up and find the circuit that is causing the amp draw. It would be helpful to know the amount of draw by using an amp clamp style meter. You can often use your DVOM in the amp mode in line with the battery cable but most meters have a 10A fuse that will blow if you put more than 10 amps through the meter.

You might want to do some studying and research on how to find a parasitic draw that is draining the battery.
Dude,I'm not a teenager working on their first car, I am a very knowledge mechanic. 35 years old now ,started working on cars at age 15.
I'm going to try to be delicate here ,I obviously don't have more information for you to describe what I'm doing/done/need to do, and you aren't giving me any information that I can use , or that I don't already know. I know how to use my Fluke 115, and I know I'm just a few tests away from finding my issue. But can't run those tests if my battery goes from full charge to 0 Volts in 90 seconds when the circuit is completed,and though I am not now nor have I ever been an automotive electrician, and I never had to bother with electrical systems when I was in the industry. So I ask that you understand that spewing out basic electrical theory and what the settings on my MM are for isn't helping me because I know the basics well enough to turn the dial and change my positive lead to the 10 amp post, but not enough to know what I can do without a complete circuit

There's more going on here than a non-denso reman alternator, and at this point it doesn't matter about the vtec solenoid gasket causing oil to leak onto the alternator, I need to find what's grounded or shorted yes, but I also need to know what tests to perform on what components I haven't already done/tested because the method I WOULD be using wont work if I cannot hook up my battery to complete the electrical circuit.

Are we on the same page now? If you have a question for me please make it something non-plebeian ,because answering you with "If you had a Fluke you'd know what MVDC is." bothers both of us I'm sure.
 

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Well, you aren't getting very far, are you. Good luck. Hope you figure out your issue. I'm done here.
 

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actually, I've gotten quite far, I've determined I have proper battery voltage , and the battery tested good at the dealership, I've determined that my arcing issue isn't an issue if I disconnect the positive from the main engine bay fuse box indicating an issue lies somewhere within ,I've determined that, my voltage at ground measures about half what it should be indicating a bad ground as well. A compound issue. As well as the power steering pump being oily and some gunk under the vtec solenoid there's a lot of possible culprits that lead to an alternator frying within an hour of use,and I understand how to address them before even thinking about installing another alternator. But yeah thanks for all your help.Please feel free to tell me what to do next my sagacious friend.
 

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And just for the record, my meter collection, along with several not even pictured here. Hmmm, what's that yellow one?

155975
 

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My Fluke (and yours) has an mVDC scale but no MVDC scale. 2.0 MVDC would be 2.0 Megavolts. Your Fluke has a millivolt scale (mVDC or mV plus the DC voltage symbol) and you're saying you read 2.0-2.2 millivolts? And yet you also said your battery drained from 12.46 to 0v in 90 seconds so where did this voltage come from? 2 millivolts is 2 thousandths of a volt. Unless you're doing voltage drop testing across the fuse with a full 12-14 volts on it and current flowing then a few millivolts on a fuse means nothing. Do you know what a voltage drop test is?

It's an Internet forum. Your words are important as nobody can be there with you to help you and see what you're doing. You have to describe what you're doing, what you're seeing, etc. and the exact words matter. I've led 2-3 people through fairly complicated electrical testing to a confirmed diagnosis at the end, just in the last few weeks here.

And, just for the record, a bad ground would not give more arcing at the battery. It would give less.
 

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Tis what I'm thinking,do I just touch leads to the housing and that lead connector at the top of the nator and read continuity?
I'm sure you know this since you've been working on cars for 15 years but did you know that between that battery wire connection and the alternator case is a diode pack? Voltage will flow one way but not the other. If you have continuity both directions (swap your leads) then the diodes in the alternator are shorted.
 

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Lastly, did you have this battery checked out before or after driving it with the alternator wire loose and the battery light on? A battery going from 12.46 to 0 volts in 90 seconds sounds like a bad battery to me. If it drained that quickly due to current flow you would have melted your wiring already.
 

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Discussion Starter #17
LOL Dude I bet if I line up all my ratchet extensions they'll be longer than yours.
can we put our genitals and measuring devices away and figure this out?

The battery was tested at the dealership after the alternator failure and replacement.the battery has held voltage being connected to the positive lead without any issues for a few days now. Is the battery bad? Not bad enough to warranty through the dealership.

Is the ground good? Well considering I'm reading just over six volts at the engine and 12+ at the battery that's suspect.

are you going to continue to attack me or give good info, a. a voltage drop test isn't a voltage drop test if your battery isn't hooked up completely, I tested continuity because if a fuse tests OL then it's obviously need replacing, I tested the "mVDC" (there ya go sugar) to see if any of the fuses I could test were in fact drawing more/less/none at all than the rest, why? BECAUSE THE BATTERY DRAINS IMMEDIATELY WHEN THE CIRCUIT IS COMPLETED. for the last time, I would have other tests to perform if fire and the lack of a fully charged battery could be helped.
 

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Now oddly enough when I test from battery to engine i get 10.5 volts today, at the fusebox i get continuity from positive in to positive out, I replaced every blade fuse in the tray, some read battery voltage some read half a volt less others were oscillating between .1-.3 voltsdc before fuse replacement steady .5 after.
continuity at the positive in lead and lead to the alternator was 250-400+ ohms of resistance. 256 ohms at the alternator itself.
 

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Hey, it's a technical issue and and not a macho thing. You may not think it's a big deal between Mega and milli but it is.
 

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I understand the difference, however my error in abbreviations isn't fixing the car when it's addressed on a forum, may I suggest discarding airs and suggesting viable tests to perform so as to narrow down my issue? You may of course enlighten me with the metric system and from which terminal electricity leaves the battery,may I please waste more of my time pointing out again that the suggestions I have received so far are "DENSO" "GIT-GUD" and "HERE'S MY COLLECTION OF GUNS" hyperbole aside after I fix this problem (whether I gotta replace the whole fuse box and wire harness to do it) would be easy to track down if instead of suggesting I watch youtube videos about how to find a short ,someone would be able to suggest a wiring diagram ,and maybe a diagram of engine ground points so that I may be thorough in my analysis without having to spend 12 hours dicking around in 100 degree heat bumbling my way through it. I swear its like you guys are being trite purpose, like I'm talking to a bunch of Gollums riding howler monkeys screaming "MY PRECIOUS!!!!!ONLY DENSO MY PRECIOUSSSSSSS"
 
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