Hello!

I own a 1993 Honda Accord EX. A few days ago, as I started the car and it barely started, as though it were on a low battery. As I was driving the radio cut out when I turned on my turn signal and the speedometer kept dying. I parked the car and tried starting it again. It wouldn't start. I realized the alternator seemed to have died.

Today I opened the hood and started removing it. There are two electrical connections to the alternator. One is a large bulky connection with four plugs, another is a small 10mm bolt. I've removed the alternator before and this 10mm bolt and its attached wire has always been very clean. This time it was massively corroded and the circle for the wire was broken. In other words, I believe the corrosion destroyed the connection between this wire and the alternator.

Keeping in mind that high voltage can cause corrosion, any ideas what is going on? Is this 10mm-bolt wire a ground or 12V positive? If I replace the connection, will the problem be fixed or will I need to replace it again when the new connection corrodes? Keep in mind that this connection is protected by a rubber "igloo" looking protector.

Thanks so much for your help!

 

How old is that boot? As old as the vehicle? May be that the boot is old and needs to be replaced. I would replace/make a new connection, cover it with grease and put that boot, or a new one, back on. As a matter of fact, it's a good idea to cover all exposed connections with grease every year or two, depending on the climate where you live.

 

I suppose the battery could be leaking so bad that it transferred to that bolt. That bolt is the main power feed to the battery. It goes through the fuse box assembly under the hood and to the positive battery post. How does the positive battery terminal look ? That post is always hot...you always want to remove the negative battery terminal when working with the alternator because you can very easily arc from that 10mm bolt to ground and cause a nasty shock. I've done this. lol

can you take a picture of it, I haven't heard of that happening before. I suppose if your hood is somehow leaking water somewhere inside even if not directly over the alternator it would cause that problem as well.

 

To holmesnmanny: I will take a picture of it. Thank you for your help identifying the wire to that bolt. I did disconnect the negative terminal of the battery. Actually learned this the hard way once myself. The colors of the spark were mighty pretty but I don't feel like repeating that.

To lazlong: I live in Indiana and go to school in Tennessee. Doesn't seem like the climate would be too harsh here. The boot seems to be in good condition, doesn't seem like that would be a problem. But I did buy some dielectric grease to put on it when I finish repairs.

I will take a picture. I am also going to try to repair the connection and then see if I can get some voltage readings to identify if the alternator is functioning properly.

Any ideas what fuse the alternator is connected to? Also what is the actual function of this wire (the one connected to the 10mm bolt)?

Thanks!

 

It's a big 80A fuse. Can't really miss it. Like I said, this wire goes straight to the battery and is what charges the battery. That's why it's always hot at the alternator.

 

Hello!

I made a new makeshift connection for the alternator, and jumped the car and was able to run it for a few minutes. I was curious if the alternator was truly functioning, so I turned on all the power-drawing accessories (brights etc.). This caused the insulation on the makeshift connection to start smoking, so I cut the power (should have realized that I would need a more highly rated wire (80Amps!)).

I think I just need to get a new crimp connection and this might be a solution.

For kicks, I tested the voltage difference between the alternator and the positive terminal of the battery, and found no voltage drop. Also checked the fuse and it looked good.

How should I verify that the alternator is truly functioning properly? test the current to see if it is truly 80 Amps at maximum power draw?

Thanks.



Pictures:

 

As a temp test I would just take it down to autozone. Normally I would think their tests suck but it will atleast tell if you if it is dead. If it tests fine it could still be bad but if it tests bad you know it's bad.

The only other way is to use a tester for amp meter...there's another word for it but I forget atm.

 

I have a multimeter I would like to use that. Do I just turn on all the power drawing accessories and then test to see if the current is close to 80Amps? (The alternator is 80 amps)

Thanks

 

Please ignore the last question, found this:

 

I like ericthecarguy. He has the best vids for compression and leakdown testing

 

A standard multimeter will not be able to do an amp test dude, it will burn out. You need one that can specifically test for it.

 

^^ Depending on the limit of your multimeter, that is right. To get around that, you can a clamp lead or get a clamp multimeter. Either one can be had for less than $20.

 

I think I fixed it! Just needed to get rid of the old ring connection and replace it with a new one. Put some dielectric coating on the new connection just to e sure. Checked the voltages mentioned in the first few minutes of the eric the car guy video and everything seemed normal. (Resting Battery voltage ~12V, Running Idle Battery voltage ~15V, Running with load Battery Voltage ~13V). Also the voltage drop across from the positive battery terminal and the alternator itself was about 0.3V.

Thanks for your help!

 

sounds good, thanks for updating

 

Hello everyone,

Well yesterday this problem recurred. I lost connection to the alternator due to corrosion at the terminal and the wire most near to the terminal.

1. Could this be an ECU problem?
2. I checked the ground for the vehicle, no corrosion or signs thereof.
3. I suppose this could be a result of a bad fix on my part causing there to be extra resistance and thus corrosion at that point.
4. I would consider replacing the entire wiring harness but it seems to also connect to just about every component in the vehicle and this seems risky.

Any other ideas?

Thanks!!

 

can you make a very good video showing the alternator and just go around the battery and your engine bay including the engine fuse box assembly(inside) so we can see what's going on ?