2000 Civic Dx - Battery OK but No Electrical Power
 

This issue seems to me entirely spontaneous - I haven't noticed anything that could have led up to this. I started and drove the car just fine this morning both to and from the gym and to work. When I went to leave work for lunch at noon, the car wouldn't start.

Description of problem:
The car won't start or even try to turn over. After it has sat for a few minutes, the accessories come on when the key is in the accessory position, but as soon as I turn it to the start position to try to start the vehicle, everything dies, and there is no electrical power on board. Even when I put the key back into the accessory position, they won't come on until the car has sat for a few minutes again.

Things I've done:
-Jump start - I had someone try to jump start my car. It behaved the exact same way as above when connected over the jump leads
-Battery test - battery label is 11/18 (very new), and I had it tested at AutoZone. It has a full charge and is working properly. Also when on the car, the voltage between the terminals reads ~12.5V
-Check battery connections - I tested the cables to make sure there were no rips, tears, or otherwise bad connections between the battery terminals and the cable connectors, the cable connectors and the actual wire strands (crimped connection), and the cables to the leads in the under-hood fuse box. Everything checks out just fine

Things I'm theorizing about:
-I believe the alternator is perfectly fine. The battery has a full charge, and the only place it would have gotten that juice is from the alternator when I drove it this morning
-I don't think the starter is at fault, but I'm not positive. There have been days where it turns over a few times more than other days before starting, but it always sounds strong. The starter doesn't ever sound weak or click like it is going bad. Again, I could be wrong here, but it started just fine three times today without any indication of beginning to fail, so I'm thinking it's probably good
-No loose/wires deeper in the wiring. The behavior is repeatable. Everything has power until the key is turned to actually start the car. When that happens, it all goes dead. After a few minutes of sitting, battery power is restored and the accessories come on again. Then, it all goes off when the key is turned to start the car. This repeatability, especially with nothing being moved, suggests a different issue than loose or intermittent connections

Now I have no idea what to do :(
I've checked what I know how to check. Please advise - am I wrong about any of the stuff above? Is there something else that could be causing this behavior? I don't have any idea what could be causing it to do what it's doing.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Ignition switch probably,

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

You need to get a voltmeter and measure across each junction and wire to find out where the voltage is being lost. Visual inspection is not adequate since no one can see electricity.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Does the starter crank the engine if you apply voltage from the (+) battery post to the starter solenoid terminal?

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

I haven't done this, no. I'm going to pick up a new switch (it's $30) and put that in first, as suggested above. If that doesn't work, I'll see if I can check out the starter this way

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Be smart. Test the switch rather than replace it. Let test results guide you.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Thanks. I'm going out now to do this, and I'll post again when I get back. I appreciate the help, all.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

I tested the connections in the ignition switch harness according to the test procedure given in the second post on this thread:
https://honda-tech.com/forums/honda-...civic-2836634/

Continuity checked out OK between the indicated terminals in each key position. To me, that seems like the switch is functioning fine. Am I misinterpreting this? I haven't put the new switch in yet (I'd like to return it if I end up not needing it).

I also made a vague attempt to check the stater, but I didn't really know what I was doing. There are three terminals on the starter solenoid, and all three have continuity to the positive terminal on the battery.
In the video linked above, at 1:14, the guy uses a momentary switch to make a connection between the starter power wire and the solenoid wire. Is this a valid test I could do to check the starter function? I've taken a picture of the connections I have on my starter, and I'm not sure which one is which.

https://cimg1.ibsrv.net/gimg/honda-t...fd5f8d0d4f.jpg

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

I can't get anything to happen when I bring power over to the starter, either from the power cable on the starter or from the battery itself. I'm jumping from either of those cables to the solenoid cable on the starter, and nothing happens.

The battery still has a full charge.

I ran through the ignition switch test as outlined in the second post in this forum:
https://honda-tech.com/forums/honda-...civic-2836634/
Everything checked out OK. The connections between the indicated terminals on the wire harness for each key position all showed continuity when the key was in the specified position. I assume this means the switch is working properly.

Also, now even the accessories aren't powering on, as they did before. There is no beeping to indicate the key is in the ignition, no accessories have power when the switch is turned to pos 1, and it, of course, still doesn't crank over when turned to start. It's like the battery is completely isolated from the wire harness. But things still show continuity to the battery terminals.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

There's a large power cable on the starter motor that runs to the (+) battery post. What is the voltage at the cable attached to the starter motor when you use the (-) battery post as ground? Compare voltage reading to voltage read between the (-) and (+) battery posts.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

My dad came out to help me work on it. After looking over the starter, we decided it wasn't functioning as it should, so I got a new one and put it in. That still didn't solve the problem.

Even though the ignition switch checked out OK, I put the new one in anyway (by this point I'm no longer thinking logically - more like just do whatever I can think of). Of course that still didn't fix it.

At one point, we had jumper cables on the battery running from dad's truck to my car, and when turning the key, sparks were flying about from around the battery/fuse box, but I had to cover on the box so I couldn't actually tell where they were coming from. They very well may have been coming from one of the fuses, but all fuses inside that box are perfectly fine.

Right now he's taking the car over to their farm, which is about 2 hours away from where I live. He has more room and tools to work on stuff like this, so he might have a better shot at getting it worked out. Any other suggestions you all have would be appreciated, though. I'll forward them on to him and see what he can do.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

What about your battery having an internal short ??? Try another known good battery.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Something has a bad connection. It almost seems like an issue in the dash fuse box or the ignition switch wiring.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Buy a multimeter to discover happiness.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Seriously...I get tired of just suggesting parts sometimes..

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

And make sure it’s a digital one.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Had this problem before. My fix was a bad ECU. Could be main relay as well

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

I don't think you actually read the first post.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

Thanks for all the advice. I haven't been spitefully ignoring your posts about getting a multimeter and testing voltages at various locations in the wire harness, I'm just ignorant on that subject. I do have a DMM and have been using that to check battery voltage supply and continuity through fuses and across major wires I have easy access to. I've checked the main battery fuse in the under-hood box as well as other, smaller fuses, and all look OK. I've also checked continuity through the wires going to the fuse box from the battery, from the battery to the starter wires, etc, and all seem to be fine.

I forgot to measure from the negative battery post to the positive lead on the terminal. I'll see if my dad can measure what that is, though I suspect, since across the battery terminals it reads ~12.6V and there is a good connection between the battery positive and the starter positive, it will also read ~12.6V. I'll let you all know.

Regarding checking voltages at the wire harnesses inside the car, this is where I'm intimidated by the amount of wiring there is. I don't know what to look for, which wires should have what voltages, etc. I've been trying to avoid having to get into all that, hoping there was a different solution. I know that's frustrating for you all, though, so I apologize.

One other thing - many people have suggested the main fuse, and some other videos I've found describe a very similar problem, although in newer model civics, and their solution was to replace the main fuse. When I measured the fuse on my car, it checked out for continuity. Is this a true fuse, which overheats and breaks apart when under too high a current, or does it act more like a circuit breaker, with a contact that moves away to open the circuit if it sees too high a current?

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

If you're getting power to your dash when you key ON then it can't be your main fuse. If you want to check the main fuse you can check voltage on both ends of the fuse.

Re: 2000 Civic Dx - Battery OK but No Electrical Power
 

check your clutch sensor it has a plastic stopper that breaks maybe its just a 4 dollar fix