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Discussion Starter · #21 ·
So I have continuity from line 7 in EA1 to its corresponding connection in the alternator plug. Decided to test the "slots" that the fuses plug into, and the alt sencing fuse contact points have no continuity. So it looks like that's my problem. Ever seen anything like that before? Seems really strange to me
 

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Discussion Starter · #22 ·
Are you able to see wire colours? They should match up but if not.
Pin 1 being the horizontal one closest to the clip/bottom of the photo should got pin 17.
Pin 2 being near your thumb, pin 7
Pin 3 being the opposite pin 4.
Hate to bother you about this more, but do you have any other ideas for things to test? I'm a little stumped why the battery isn't charging when I have continuity in all lines
 

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So I have continuity from line 7 in EA1 to its corresponding connection in the alternator plug. Decided to test the "slots" that the fuses plug into, and the alt sencing fuse contact points have no continuity. So it looks like that's my problem. Ever seen anything like that before? Seems really strange to me
Can you explain what you mean? If you take the fuse out and try test the slots it goes into you will never get continuity.
 

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Hate to bother you about this more, but do you have any other ideas for things to test? I'm a little stumped why the battery isn't charging when I have continuity in all lines
Ok so we know the wiring from the engine bay fuse box to the alternator is good.
Is it OK back to the rest of the car? You should be getting 12V through 7 and 17 when the ignition is ON. I believe pin 4 should also have 12V in that situation although when the car is running this shuts off? I've never actually done this test before.
 

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Discussion Starter · #26 ·
Ok so we know the wiring from the engine bay fuse box to the alternator is good.
Is it OK back to the rest of the car? You should be getting 12V through 7 and 17 when the ignition is ON. I believe pin 4 should also have 12V in that situation although when the car is running this shuts off? I've never actually done this test before.
Not an issue. I'll look into tonight and see what I get for voltage as well
 

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Discussion Starter · #27 ·
Ok so we know the wiring from the engine bay fuse box to the alternator is good.
Is it OK back to the rest of the car? You should be getting 12V through 7 and 17 when the ignition is ON. I believe pin 4 should also have 12V in that situation although when the car is running this shuts off? I've never actually done this test before.
So this looks to be the issue. Turned the ignition on and tested 7 and 17 and got no voltage. Same for testing 4 and 7 as well as 4 and 17. Looks like every possible combination doesn't have voltage. Didn't even go through with testing with the engine on since it wouldn't tell me anything different in this case. Figured I might as well try a continuity test afterwards and found that 7 and 17, 4 and 7, and 4 and 17 all had continuity as well. Not sure if it was a meaningful test, but it didn't hurt
 

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So this looks to be the issue. Turned the ignition on and tested 7 and 17 and got no voltage. Same for testing 4 and 7 as well as 4 and 17. Looks like every possible combination doesn't have voltage. Didn't even go through with testing with the engine on since it wouldn't tell me anything different in this case. Figured I might as well try a continuity test afterwards and found that 7 and 17, 4 and 7, and 4 and 17 all had continuity as well. Not sure if it was a meaningful test, but it didn't hurt
So you tested from 7 to ground/chassis? And again 17 to ground/chassis?
Testing between them will not give you the correct results.
 

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Discussion Starter · #29 ·
So you tested from 7 to ground/chassis? And again 17 to ground/chassis?
Testing between them will not give you the correct results.
Aha I see. Ok I need to test chassis ground to wire and not in between wires. That makes sense there. Will definitely try testing that way instead. Just having a hard time understanding if chassis ground truly means that anywhere touching the chassis works or if there are specific parts on the chassis that have grounding points. I have this diagram which shows EA as a ground point, but I've looked through the engine bay and trunk with the liner out and haven't seen anything that looks like EA which has me a little stumped
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Aha I see. Ok I need to test chassis ground to wire and not in between wires. That makes sense there. Will definitely try testing that way instead. Just having a hard time understanding if chassis ground truly means that anywhere touching the chassis works or if there are specific parts on the chassis that have grounding points. I have this diagram which shows EA as a ground point, but I've looked through the engine bay and trunk with the liner out and haven't seen anything that looks like EA which has me a little stumped
View attachment 83259
You can ground to any unpainted surface on the chassis or even the engine.
The electrical system uses the chassis as a ground. The whole chassis is electrified as is the engine and gearbox.
Power goes from the battery, through the wires to the electrical system and to complete the circuit the chassis and engine is used to send it back to the ground strap back to the battery.

For this test I would use a nut on the suspension tophat. Or the bolt on the wire connected to the engine bay side panels.
 

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Discussion Starter · #31 ·
You can ground to any unpainted surface on the chassis or even the engine.
The electrical system uses the chassis as a ground. The whole chassis is electrified as is the engine and gearbox.
Power goes from the battery, through the wires to the electrical system and to complete the circuit the chassis and engine is used to send it back to the ground strap back to the battery.

For this test I would use a nut on the suspension tophat. Or the bolt on the wire connected to the engine bay side panels.
Ok awesome. Thank you so much for taking the time to explain some very basic concepts

Just tested each wire to the chassis ground with the ignition on and still wasn't getting any voltage. Tested for continuity and everything was looking good there, so it looks like something must be up with those wires. Again, didn't test with the engine off since wire 7 already isn't getting voltage

Looks like that's the issue there, now it's just time to fix it...
 

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Ok awesome. Thank you so much for taking the time to explain some very basic concepts

Just tested each wire to the chassis ground with the ignition on and still wasn't getting any voltage. Tested for continuity and everything was looking good there, so it looks like something must be up with those wires. Again, didn't test with the engine off since wire 7 already isn't getting voltage

Looks like that's the issue there, now it's just time to fix it...
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.
 

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Discussion Starter · #33 ·
Ok awesome. Thank you so much for taking the time to explain some very basic concepts

Just tested each wire to the chassis ground with the ignition on and still wasn't getting any voltage. Tested for continuity and everything was looking good there, so it looks like something must be up with those wires. Again, didn't test with the engine off since wire 7 already isn't getting voltage

Looks like that's the issue there, now it's just time to fix it...
Sorry, meant to say "with the engine on..."
 

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Discussion Starter · #34 ·
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.
Definitely a smart idea just to make sure that the test is working correctly. Just to confirm though 1) when you say plugs that means EA3 and EB1 in this case? 2) Since the plugs need to be plugged in, I should pierce the insulation on that wire to get the voltage reading (and again just run the other probe to a chassis ground)
 

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Definitely a smart idea just to make sure that the test is working correctly. Just to confirm though 1) when you say plugs that means EA3 and EB1 in this case? 2) Since the plugs need to be plugged in, I should pierce the insulation on that wire to get the voltage reading (and again just run the other probe to a chassis ground)
You can push the probe into the plug touching the terminal, no need to pierce the insulation. There are not many situations where you would have to do that.
 

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This is actually a photo from 2 years ago but it sort of shows what I have been trying to explain.
Plug it in and push the probe into the hole with the terminal on the end of the wire. It will contact the metal terminal and provide an electrical connection to the multimeter. Then touch the black probe to the engine or a bolt on the chassis.
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Discussion Starter · #40 ·
This is actually a photo from 2 years ago but it sort of shows what I have been trying to explain.
Plug it in and push the probe into the hole with the terminal on the end of the wire. It will contact the metal terminal and provide an electrical connection to the multimeter. Then touch the black probe to the engine or a bolt on the chassis.
View attachment 83275
Ahhh ok I see now. Thank you so much, that makes perfect sense. Should be testing that later today and letting you know the results
 
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