New alternator -03 not charging

[Tom Kay]

Hi, would really need some good advices.

Wifes yaris had a dead Battery, they jump started it and she got back home with it.

I checked the voltage with a multimeter and it was not charging (12,2)

I turned the engine off, and turned it back on, now it was charging (13, something)

It was charging about half the times when you turned it on, so i changed the alternator (lucas rebuild)

But now with the new alternator it is not charging at all, meaby if you start the engine 40 times it will charge one time (13,2)

I have measured directly from the alternator +B terminal (not charging, I have measured from the alternator multiplug, all 3 terminals have 12v when ignition is turned on. I have checked that the alternator is getting ground. 

Battery light comes on in the dash when ignition is turned on, but it has never lighten up when engine is running, and the car is not charging, i think thats odd.

I did found this old topic, with the exact same problem, but no-one never came back to tell what was the problem-> 

 

[Tom Kay]

I did found this wiring diagram from the net, but I think it is for a newer model, because that alternator has 4 pins+B, and my only has 3 pins+B.

But I did check the IG pin from the alternator to the 10A gauge fuse, and the wire was good.

L pin I was not able to check, because i did not find that 7,5A MET fuse, but the pin is getting 12v when ignition is turned on, and the Battery light does not come on when ignition is turned on when this pin is unpluged, so I guess it is good.

Also the M pin i was not able to check, the schema says it goes to the engine control module, i did found engine ecu from the passengers side footplate, but there was no pin numbers, so i tried every pin from the ecu but none of them beeped with the multimeter, but again, the M pin is getting 12 when ignition is turned on, so i guess it is good also.

[Mooly]

Almost impossible to diagnose this at a distance but the stand out clue is that both the original and the replacement alternator have according to your measurements been able to charge at least some of the time, even if it was one just start in 40.

Hazy thinking... could it be a fault/intermittent ignition switch?

What happens to the Battery voltage if you turn on addition electrical loads such as headlights? Again hazy thinking, could the Battery have high internal resistance and that is causing the alternator output to be reduced as the voltage is actually spiky in nature and not a more pure DC value.

 

[flash22]

The 3 wire setup is very common (not ecu controlled)

Right to left - B+, Sense, Ignition, Warning light (oval plug)

Make sure the plug is clean and tight and the pins haven't been spread apart - make sure the alternator is getting the 12v IG (switch live)

 

Does your wife have a large bunch of keys with her car keys ?

[Tom Kay]

7 hours ago, Mooly said:

Almost impossible to diagnose this at a distance but the stand out clue is that both the original and the replacement alternator have according to your measurements been able to charge at least some of the time, even if it was one just start in 40.

Hazy thinking... could it be a fault/intermittent ignition switch?

What happens to the battery voltage if you turn on addition electrical loads such as headlights? Again hazy thinking, could the battery have high internal resistance and that is causing the alternator output to be reduced as the voltage is actually spiky in nature and not a more pure DC value.

 

I have tried it with a new Battery, but the the problem is still present.

When i leaved work with it, without load the voltage was 12,9-13,1v

With load it dropped to 12,7v. When i was home, I turned the engine off and started it again,

and then the voltage was without load 12,7v

with load 12,2v. The voltage drops step by step when i turn on more load.

 

That diagram what I posted was wrong, I bought the right workshop manual, and was able to test all the alternator cables and everyone was good (i will post the right diagrams, for the next poor guy why wonders why his wifeys ****box wont charge XD).

[Tom Kay]

7 hours ago, flash22 said:

The 3 wire setup is very common (not ecu controlled)

Right to left - B+, Sense, Ignition, Warning light (oval plug)

Make sure the plug is clean and tight and the pins haven't been spread apart - make sure the alternator is getting the 12v IG (switch live)

 

Does your wife have a large bunch of keys with her car keys ?

Well actually the M pin goes to the ecu, that signal tells the alternator how much there is load, so it can adjust the charging voltage, standard value for this signal is 11-14v, I need to measure this when the engine is running, if that is okey, I think the next step is just change the alternator again, everything has been measured what can be measured.

[Tom Kay]

[Mooly]

Has the car actually failed to start since you fitted the new Battery and alternator?

In other words has it gone flat again?

If not then I'm wondering if something is wrong with the measurement results rather than a real fault. Are you sure the meter is giving accurate and consistent results?

 

 

 

[Tom Kay]

No it haven't because now I drive it just to work and back (10km) and every night I have charged the Battery with a charger.

I have a voltmeter in the cigarette slot so i can inspect the voltage when i drive. And a multimeter when i troubleshoot it home, and both are giving the same value.

 

Today the voltage was just 12,2, and there was no impact if I turned loads on and off, so it is also inconsistent.

 

My plan is today that i will try to benchtest the old alternator and find out what pins does the alternator need. So meaby I can bypass the multiplug and see if the new alternator starts to charge, and if that doesn't do the trick I'm out of ideas.

[Madasafish]

Sorry if you have already done this, but first thing I would do is undo , clean and redo all earth leads to Battery and body.And the live leads as well.

 

 

[flash22]

Those diagrams are not correct for your car

 

 

[Tom Kay]

1 hour ago, Madasafish said:

Sorry if you have already done this, but first thing I would do is undo , clean and redo all earth leads to battery and body.And the live leads as well.

 

 

I did this for the chassis, and was planning to do it for the engine yesterday but it was so tight place so i was not able to open it.

BUT NOW.... I jumpwired the negative Battery terminal to the alternator frame, and it started to charge. I feel so dumb right now.

 

Pretty sure I won't do the interior reassembly without beer today 😃

[Tom Kay]

53 minutes ago, flash22 said:

Those diagrams are not correct for your car

 

 

Yeah I know that those are for Verso and Echo, but everything was correct, except some pin numbers were different, but the color codes where the same.

[Mooly]

So you have found the problem by the sound of it, a high resistance connection/lead somewhere... excellent.

[Madasafish]

Well done...

[stantheman1]

5 hours ago, Madasafish said:

Well done...

I think a 'Thanks' would go down well from the op.

[fotinopoulos67]

On 4/30/2021 at 4:44 AM, Tom Kay said:

I did this for the chassis, and was planning to do it for the engine yesterday but it was so tight place so i was not able to open it.

BUT NOW.... I jumpwired the negative Battery terminal to the alternator frame, and it started to charge. I feel so dumb right now.

 

Pretty sure I won't do the interior reassembly without beer today 😃

How did you go about jumpwiring the negative Battery terminal to the alternator exactly? you use jumper cable or just a basic 16 gauge wire? 

Thanks in advance

[stantheman1]

Just temporarily use a jumper lead for ease of access Angelos.