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Discussion Starter · #41 ·
No problem.

Can you try the same test with the big Black w/Red strip wire in Pin 1 of EB1 just to confirm you are actually getting a reading and your tests are correct. This wire should have a voltage though it with the ignition ON. It has nothing to do with the alternator. You will need to have the plugs plugged into the fuse box for this to work.
Connected EB1 and EA3 and can confirm that I'm getting voltage from the black & red striped wired in EB1 to a chassis ground with the ignition on. Did want to ask though, I used pin 4 though instead of 1, since pin 1 doesn't have a wire and the female end of EB1 doesn't have a metal protruding terminal for pin 1 (like the terminals sticking out of EA3). Hope everything's good here though since I did use the black and red striped wire
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Discussion Starter · #43 ·
Ah yes. The 5SFE doesn't have pin 1 populated. That is fine as it is the same wire.

Now to test the other wires for the alternator. Good work!
Perfect and thanks so much! Assumed it was good, but definitely didn't hurt just to check. Definitely wish I had the 3s-gte though haha. Maybe one day but not while I'm learning how to drive a mid engined car...

I'm reading this post and it sounds like just turning the ignition on and testing voltage from each terminal in the alternator plug to a chassis ground will do?
 

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Discussion Starter · #45 ·
Yes that will be a suitable test.
Perfect. Just went ahead and did that test and got voltage from all 3 terminals. I believe it's pin/terminal 2 (it's the one that has continuity with pin 4 in EA3. Think that's #2 if I remember correctly) had a lower voltage than the other 2 pins. 11.8v at that pin vs 12.3v at the others (I only have 12.5v at the battery currently). It seems a little low but not sure if it's too big of a drop to be an issue or not
 

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You will get a voltage drop between the battery and the back of the car. How much drop depends on the wire size and length.

So we can assume that you have 12V or similar at the 3 pin alternator plug as you were getting continuity of all 3. Test anyway. Have EB1 and EA3 plugged is as before and unplug the 3 pin plug from the alternator and do the same voltage test of all 3.

If they all come back with 12v or similar to your other tests then we need to look at the alternator itself. You should also get 12V on the alternator main cable. Both at the alternator and at the fuse box in the engine bay. It's the one with the red + cap on it.
 

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Discussion Starter · #47 ·
You will get a voltage drop between the battery and the back of the car. How much drop depends on the wire size and length.

So we can assume that you have 12V or similar at the 3 pin alternator plug as you were getting continuity of all 3. Test anyway. Have EB1 and EA3 plugged is as before and unplug the 3 pin plug from the alternator and do the same voltage test of all 3.

If they all come back with 12v or similar to your other tests then we need to look at the alternator itself. You should also get 12V on the alternator main cable. Both at the alternator and at the fuse box in the engine bay. It's the one with the red + cap on it.
Good to know there

Ok so last night I was testing with EA3 and EB1 plugged in. Just did a test today and with them not plugged in and I don't get any voltage between the 3 plugs and a chassis ground. Plugged them back in and get voltage like normal. Does that change anything by chance?

So would that be a test from each pin in the alternator plug to the wire with the red + cap on it as well as a test from each pin in the alt plug to the top bolt on the alternator? Just trying to make sure I understand that correctly
 

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Discussion Starter · #49 ·
Just up voting the testing of fuses with ohmmeter vs eyeballs. I recently wasted 4 hrs at a friend's house who told me that the "fuses were OK"; but when everything else was also OK, I checked the fuses myself with the DMM.....hmmmm.
Not a fun learning process and thanks for the tip there! Did a test on them a few days back and for better or worse, I did have continuity on all fuses. Wish it was that simple in this case
 

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Good to know there

Ok so last night I was testing with EA3 and EB1 plugged in. Just did a test today and with them not plugged in and I don't get any voltage between the 3 plugs and a chassis ground. Plugged them back in and get voltage like normal. Does that change anything by chance?

So would that be a test from each pin in the alternator plug to the wire with the red + cap on it as well as a test from each pin in the alt plug to the top bolt on the alternator? Just trying to make sure I understand that correctly
When you unplug them they will not have any voltage. You have disconnected them from the car/battery. They get voltage from the fuse box.

This might help you understand things a bit better.

To test voltage of a circuit you need to have one probe of the multimeter (red) on a power source and the other (black) on a ground point.

What I need you to do is probe the each pin of the 3 pin alternator plug with the red and keep the black always on the ground point/chassis. The main alternator cable at the alternator will have the red probe touching it and the black probe to ground. If you touch two power sources you will not have a circuit and therefore no voltage showing.

Point EA4 is the red + cap connection.

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Discussion Starter · #51 ·
When you unplug them they will not have any voltage. You have disconnected them from the car/battery. They get voltage from the fuse box.

This might help you understand things a bit better.

To test voltage of a circuit you need to have one probe of the multimeter (red) on a power source and the other (black) on a ground point.

What I need you to do is probe the each pin of the 3 pin alternator plug with the red and keep the black always on the ground point/chassis. The main alternator cable at the alternator will have the red probe touching it and the black probe to ground. If you touch two power sources you will not have a circuit and therefore no voltage showing.

Point EA4 is the red + cap connection.

View attachment 83292
Ok great that's good to know there aren't any issues there

I guess I'm not understanding how this test "Have EB1 and EA3 plugged is as before and unplug the 3 pin plug from the alternator and do the same voltage test of all 3." differers from what was done yesterday. Is the difference that I need to check the voltage of each pin in the alternator plug to the chassis ground when the plug is in as well a when it is not plugged in?

And then just for this test, "You should also get 12V on the alternator main cable. Both at the alternator and at the fuse box in the engine bay. It's the one with the red + cap on it." is just testing each alternator plug pin to EA4? If so, does it matter if the alt plug is plugged in or not?

Sorry for all the back forth, but just trying to clarify to make sure I'm doing the tests correctly
 

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Ok great that's good to know there aren't any issues there

I guess I'm not understanding how this test "Have EB1 and EA3 plugged is as before and unplug the 3 pin plug from the alternator and do the same voltage test of all 3." differers from what was done yesterday. Is the difference that I need to check the voltage of each pin in the alternator plug to the chassis ground when the plug is in as well a when it is not plugged in?
Plug in EB1 and EA3 and forget about them for this test.
Unplug the 3 pin plug from the alternator and test here. Each pin is a separate test. Red probe to pin 1 and black to chassis. Pin 2 and pin 3 as per pin 1.
You do not need to test it with the 3 pin plug plugged into the alternator. Just unplugged.
And then just for this test, "You should also get 12V on the alternator main cable. Both at the alternator and at the fuse box in the engine bay. It's the one with the red + cap on it." is just testing each alternator plug pin to EA4? If so, does it matter if the alt plug is plugged in or not?

Sorry for all the back forth, but just trying to clarify to make sure I'm doing the tests correctly
For this test, it is the same as above. Touch the red probe to the stud with the 10-12mm nut on it and the black to the chassis. Ignore the fuse box for this test.

It's all good. We can work through it to get the results we need. You can upload photos and a short description of what you are doing if you feel this will help.

Do the above tests and see what you are getting.
 

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Discussion Starter · #53 ·
Plug in EB1 and EA3 and forget about them for this test.
Unplug the 3 pin plug from the alternator and test here. Each pin is a separate test. Red probe to pin 1 and black to chassis. Pin 2 and pin 3 as per pin 1.
You do not need to test it with the 3 pin plug plugged into the alternator. Just unplugged.

For this test, it is the same as above. Touch the red probe to the stud with the 10-12mm nut on it and the black to the chassis. Ignore the fuse box for this test.

It's all good. We can work through it to get the results we need. You can upload photos and a short description of what you are doing if you feel this will help.

Do the above tests and see what you are getting.
Ok great. It looks like I got that first test done already then. The two 12.3v and one 11.8v readings that I got yesterday were coming from the alt plug pins to the chassis ground. Will get the next test done from EA4 to chassis ground and get results back soon. Appreciate all the help!
 

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Discussion Starter · #54 ·
Plug in EB1 and EA3 and forget about them for this test.
Unplug the 3 pin plug from the alternator and test here. Each pin is a separate test. Red probe to pin 1 and black to chassis. Pin 2 and pin 3 as per pin 1.
You do not need to test it with the 3 pin plug plugged into the alternator. Just unplugged.

For this test, it is the same as above. Touch the red probe to the stud with the 10-12mm nut on it and the black to the chassis. Ignore the fuse box for this test.

It's all good. We can work through it to get the results we need. You can upload photos and a short description of what you are doing if you feel this will help.

Do the above tests and see what you are getting.
Figured uploading a picture wouldn't hurt for this one. This is with ignition on and engine off. EA4 to ground is showing no voltage. Tested one other ground spot as well that normally works in case I'm not getting good contact with the suspension bolt, and no voltage there too :(
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That is definitely busted.

Hindsight says, look at ALL your fuses however you've learnt a few things about the alternator system, how to test for continuity and how to test for voltage. Good effort.
 

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Discussion Starter · #59 ·
That is definitely busted.
Absolutely. Definitely gonna run to the store tomorrow and get a new fuse there. Confused though about what blew it though... Checking the alternator and it's for the right build date. Almost positive I have power steering as well, and got the alternator for specific to models with power steering...

Oh well. The details about why don't matter too much, just very strange all in all. Hopefully a new fuse is all that's needed to fix it

Seriously though. Went through the 3 normal fuses you'd check for the charging system, but obviously I should not have overlooked the main fuse for so long. All thanks to you though! Wouldn't have been able to learn it without your help. Can't say thank you enough!
 
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