Any thoughts on what would be needed to protect from back voltage?

It's all theory and supposition from me.  The starter motor might be innocent.

[Surferdude]

^^^
Theory and supposition is good.

Helps to promote more theory and supposition - and sometimes answers follow.

[steinrk]

Okay - her we go again....

I'm one of the guys that experience over and over again that the headlight blows.

Personally I do not belief in the back EMF idea. The reason is that I belief that the battery will take care of most of the EMF unless they are exceptional large

I belief that there is something wrong with the programming of the generator.

The reason is that my measurement shows that the voltage to the bulbs are more than 14 volts which is much more that the bulbs are specified for. As I have said before, the test voltage for bulbs are specified to 13.2V

I have earlier used a multimeter and checked the voltage directly on the bulbs. Today I took it one step further. I borrowed a calibrated FLUKE 189 multimeter, accessories for interfacing the multimeter to the PC and installed FLUKE View Form on the PC.

Now I can record the voltage and in that way document what is happening. All recordings below arw done with 1 sec sample interval.

The first recording was done this morning with a cold car. The temperature was approximately +9C
Recording 1 was done directly on the battery.



Finding:
The voltage before the car is started is  12.49V
Point A: The door is opened and the voltage drops a bit due to indoor light
Ponit B: The key is turned to start the glowing
Ponit C: The starter kicks in and voltage drops to below 11V due to the high current
Point D: Engine has started and generator starts to charge the battery (Why this high 14.7V ??)
Point E: Charge voltage drops to 14.3V after 1min 50 sec
Point F: Engine is stopped

Then I moved the probes to the bulb (connected directly to the bulb) and made a new recording. Here where I live the lights are always on. The only way to avoid this is to put the lights to park lights when the car is started.

As Recording 2 shows the voltage goes immediately up to 14.3V and then it slowly increases to 14.4V.
Then after 2 min and 30 sec the voltage drops down to  12.84V which I consider a more normal voltage for the bulbs.
As the chart shows I started and stopped the car 4 times to see if the voltage behaved the same way every time. Only on the two first occasions I waited until the voltage dropped down before I stopped the car.

My first question when I saw these recordings was.
Why was the voltage on the battery only dropping 0.5V after 1 min and 50 sec and the voltage on the bulbs dropping 1.5V after  2 min 30 sec?

This lead me think that the voltage to the battery and the bulbs where two different voltages. Later measurements today (using two multimeters, one on the battery – one on the bulbs) have however shown that this might not be the case. I have to do more recordings to morrow to verify this.

Anyhow, so far my conclusion is that the high voltage on the bulbs the first minutes after the car is started destroys the bulbs.
I can see no reason why the voltage should be 14.4V !!!!! There has to be something wrong with the generator and the controlling of the voltage.

I’ll try to do some more recordings tomorrow. I’m especially interested in how the generator behaves when the engine is warm.

[Dazzler]

Wow.. Great post steinrk    Go straight to Hyundai .. don't pass go, hopefully collect $200..

But seriously, Hyundai should have done this themselves by now .. I think you need to send all this info to Hyundai Head office along with a link to this thread .. (Or someone does anyway..)

[steinrk]

Wow.. Great post steinrk    Go straight to Hyundai .. don't pass go, hopefully collect $200..

But seriously, Hyundai should have done this themselves by now .. I think you need to send all this info to Hyundai Head office along with a link to this thread .. (Or someone does anyway..)

I will, but I just want to collect some more info first.....

[Dazzler]

 

[Surferdude]

That's excellent stuff.
Just one thing - and it may be a language translation idiosyncrasy but I haven't had a generator on a car I've owned for decades. They are all alternators now.
I accept they essentially do the same thing but I only mention it because if you do contact Hyundai with the above info, and refer to a "generator" will it harm your credibity to them?

Meanwhile, can someone explain to me the difference between a "generator" and and "alternator"?

[Phil №❶]

steinrk

As other have said, thank you for the excellent information. I believe that the regulator which is built into the alternator is overcompensating for the drop in battery voltage immediately after cranking the engine. As your lights are already on, they also receive this extra voltage which is too much. There is only 1 voltage produced throughout the whole car. Could you please explain how you connected your meter to the lights.

surferdude

In layman's terms (because that's what I am), a generator is essentially an electric motor in reverse. Output is roughly linear with speed of rotation. So, to charge a flat battery, you have to drive fast and long to put in enough meaningful amps. An alternator produces 110v AC and is then rectified by high power diodes to approx 14+ volts. A regulator looks after the Volts to keep it acceptable for a car. Years ago they were simply relays which were adjustable. Nowadays the regulator is all electronic and is a throw away device. The main advantage of an alternator is enormous amps output at relatively low revs, so high speed is not required 80Amp outputs are not uncommon in today's cars that's 960 watts @ 12 v. This is useful because of the increased electrical loads that exist in modern cars. 

[steinrk]

Just one thing - and it may be a language translation idiosyncrasy but I haven't had a generator on a car I've owned for decades. They are all alternators now.

..of course  , my fault

I believe that the regulator which is built into the alternator is overcompensating for the drop in battery voltage immediately after cranking the engine.

This is exactly what I'm thinking also. If this is due to voltage drop in the cables to the sensor in the regulator there is no help in changing the alternator. It's one or more cables that have to have their dimensions increased.

As your lights are already on, they also receive this extra voltage which is too much.

I doesn't matter if your lights are on or not during start up. As my recording shows the high voltage continues for more than 2 minutes. If you are going to avoid this you will need to leave the lights off until the voltage has stabilized on the correct level.

There is only 1 voltage produced throughout the whole car.

That's what I thought also but the recordings from yesterday puzzles me. Measuring on the battery; the voltage dropped 0.5V after 1min 40 sec, measuring on the bulb; it dropped 1.5V after after 2min 40 sec. This could however be coincident as I did only one recording on the battery and did not have two multimeters that would let me see both voltages at the same time.

This is why I want to do some more recordings.

Could you please explain how you connected your meter to the lights.

See attached picture.

[constipated]

If it is a wiring and resistance issue and then alternator overcompensating, it explains why it might be a hard fix. Imagine the meters of wiring within the car that are put in when the car is just a metal frame. Now it is completely built how much would they need to pull out to fix wiring problems.

It's like trying to localise a wiring fault in a house after it has been constructed.

If this is the case, I wonder why Hyundai weren't onto it much earlier and change some of the wiring they use. Perhaps not a universal cause.

But really, so many reports of it that surely Hyundai should have rectified this by now.

[steinrk]

Carried out several new recordings today and here is a summary of my findings so far.

•   The voltage on the bulbs is 0.31V lower than the voltage directly on the battery. This can be seen in Test 6 where all the recordings are done on the bulb except at point A where the probes from the battery was connected to the recorder for a short time.
•   The voltage on the bulb and the battery always follow each other. This has been confirmed by using two multimeters, one connected to the bulb one to the battery
•   At start up the voltage on the bulbs will increase to 14.0V – 14.4V. This will normally drop down to 12.4V – 13.0V after a period of 135-147 sec
•   The idle rev of the car increases slightly from 1600 rpm to 1750 rpm when the voltage drop takes place
•   During 20 recordings of voltage during start up the voltage has on 1 case stopped at 12.4V on the bulb (not going up to >14V)


My worries so far

•   Why does the voltage on the bulb go up to above 14V at startup?
•   On two occasions the voltage has only dropped down to 14.0V on the bulb. This can be seen on the first recordings carried out and posted yesterday (battery voltage 14.3V) and the Test 7 where I made a 20 minutes drive to get the car warm, and started recording the battery voltage without stopping the car. In that test the battery voltage was again 14.3V. Does this mean that the voltage has been at 14.3V since I started the car?
•   If the voltage has been at 14.3V on the battery (2.28V/cell) for an extended time, what will this do to the lifetime of the battery?

Next steps:

Make an adapter to the +12V outlet inside the car so that I can record the voltage while I'm driving.

My wish:

Get as many users of this forum as possible to measure the voltage on the battery immediately after startup and then again after the voltage drop has taken place ( wait approximately 3 min).
This will give us some info if it is only some cars or all cars that behave like this.
I think we need to know:
-   Type of engine
-   Ambient temperature
-   If the car is cold or warm
-   Voltage immediately after startup
-   Voltage after 3 minutes



A small explanation to the attached recordings:
Test 6: just a normal start/stop recording of voltage on bulb. At point A the test probes from the battery was connected to document the voltage difference between bulb and battery.

Test 7: Connected the recording to the battery after a 20 min drive without stopping the car. The recording up to point A shows that the voltage is 14.3V. At point A the car was stopped. Point B, C, D, E shows the locking/unlocking of doors. At point F the car was restarted and is running until point H. At point G the voltage drops as normal.

[Phil №❶]

Once again, excellent information.

For the purpose of testing, it would be best to make up some long test leads that connect to the same spots you are currently connecting to rather than making an adapter to work in the cabin. The cabin circuit is not a direct battery or light circuit and may introduce more variables. I did this on a different car & just ran them into the cabin through the window (not fully closed of course). It is only temporary after all.

I don't think your battery will be affected by the current voltages. They are very robust and the high voltage appears only to be a reaction to the engine cranking.

The test you are performing is very good, I wonder if also you would consider a longer test using some electrical loads eg air conditioning on high & rear window demister at the same time to introduce high load on the alternator AFTER the volts have dropped back to normal. This would test to see if at any time the regulator tells the alternator to increase volts to compensate again. If it does, then these volts are possible not only at startup, BUT WHILE DRIVING AT ANY TIME and for an extended period.

Good luck with your crusade. 

[Dazzler]

  Wonder if anyone has the gear to do exactly the same thing on a 2.0 Petrol i30 (as a comparison) I suspect these surges are a lot less prevalent 

[Phil №❶]

This is what you (almost) guessed the other day.

I think that the ignition circuit which is continuously operating (on petrol engines) is a very robust circuit and absorbs any spikes (in fact it produces them) and may be a reason why lights don't blow as frequently as diesel engined cars. My understanding is that the glow plugs do their work until the light on the dash goes out, then they no longer draw any current. It appears that the regulator is telling the alternator to output too many volts initially & with no ign circuit, diesel cars get the lot to cope with. 

[Dazzler]

Sounds logical .. I wonder if other Diesel vehicles are prone to the same issue..

[Phil №❶]

Depends on how many have to drive around with their lights on by law, in the dark, cold countries. I wonder if there's a bad batch of regulators, can't' tell easily because they're incorporated inside the alternator these days. I might try to get some readings from the wife's car (if she'll let me).

[steinrk]

Just a quick update.

Recorded the voltage from the +12V output inside the car all the way to work this morning.

• At startup, voltage was 14.7V
• After 140sec it dropped down to 14.3V
• The voltage stayed at 14.3V all the way to work >50min
• Tried to turn on air conditioning on high, rear window demister, heated seat, radio, everything to see if voltage changed. It didn't
• Arrived at work and tried to stop and restart the car again twice. On both cases the voltage went up to 14.7V and then dropped down to 13.0V.

New recording will be done on way home.

[steinrk]

Depends on how many have to drive around with their lights on by law, in the dark, cold countries.

Up here in Norway/Sweden it's mandatory to use the lights.

I wonder if there's a bad batch of regulators, can't' tell easily because they're incorporated inside the alternator these days. I might try to get some readings from the wife's car (if she'll let me).

That's why I'm so interested in getting as many as possible to measure their voltage. There is no need to do a recording. Just measure it immediately after startup and then after 3 minutes.
The more documentation the stronger the report will be.

I'm also wondering if we have the same alternator as the rest of the world? Some brands (Audi) use a larger alternator and higher capacity battery on cars sold in cold countries.

My car is equipped with a 70Ah battery. Is that the same down under?

[Dazzler]

My car is equipped with a 70Ah battery. Is that the same down under?

We only have a 2.0 Ltr Petrol CW these days which I suspected would have a lower rating...

on the top of the battery (only part visible it says)

MF48-23GL 12V RC:91MIN CCA 550A 

[Phil №❶]

It's no wonder you're lights only have a short life @ 14+ volts constantly.

European I30's are not assembled in Korea, Australian ones are. I wonder if we also have a different brand / capacity alternator. From memory, it's not easy to see but I'll try tomorrow. It's nearly dusk at the moment. 

[Phil №❶]

Today the car was driven to the city which is a 1 hour return trip.

I connected a digital multimeter to the extra power jack next to the cig lighter. Here are the results.

Status - Car had been driven recently in the last hour.

Temp 23 deg C

Minutes   Out      Return
                    Volts
Rest        12.62      12.72
Run         15.3        14.11
1             16.2        14.25
2             16.09      14.25
4             15.82      14.24
6             15.31      14.24
8             14.99      14.24
10           14.68      14.02
15           14.32      14.13
20           14.34      14.25
25           14.34      14.32
30           14.28      14.27

At this rate, looks like I should expect light problems in the near future, although we do very little night driving.

IMO this is way too high. My other car reference manuals suggest 13.8-14 as max allowable volts. I got 16.09 at 1 stage.
This means that ALL other electronics are at this voltage as well.

If the weather is cold, as it is in Europe, I would expect that 16v could be maintained for an even longer period as the battery is more reluctant to accept charging when cold.

Apart from the compensation for battery cranking, I have no explanation as to why the results are so different. I graphed it but it is too big to attach. The car was parked for 30 minutes while the city activities were conducted. I recommend you do a simple graph to see these results. Note at the 30 minute mark there is .1 of a volt difference.


If the lights begin to fail regularly, I will regulate the voltage with my own circuit.

[steinrk]

Latest findings:

• The setting of the Light Switch has a large influence on the voltage from the alternator .

Some of you might think that this is obvious but to me it's not. The reason is that since it's mandatory to use the headlights in this country the only difference by having the light switch off vs. on is:


• The light on all the buttons in the dashboard is off.
• It's possible to flash the lights but the high beam can not be turned on
• The diming of the light intensity in the instrument panel/LCD/radio is not working (always set to max)
The headlights are on in both cases. I've included two pictures below to show the difference seen from the driver position.

Due to this small difference up to yesterday I didn't really pay a lot attention to if the light switch was off or on. Now I know that this is important.

Coming back from work yesterday I couldn't understand why the voltage sometimes dropped 1.5V after 130-140sec and sometimes not. So I decided to do some more recordings and then it became clear.


• If the light switch is turned off (set to 0) - the voltage drops 1.5 V after 130-140sec
• If the light switch is turned on - the voltage drops only 0.5V

This can clearly be seen in the attached recordings:


• Test 8a, home -> work, light switch on: Voltage drops from 14.7V to 14.3V and stays very stable for the whole ride. Arriving at work I stopped the car and turned the light switch off (due to habit) before I did 2 attempts to restart the car. In both these cases the voltage dropped to 12.9V
• Test 8B, work -> home, light switch on: Voltage drops to 14.3V but then after 10min it starts to toggle between 13.6V - 14.2V - 14.7V
• Test 9, stop/start driving: This was when it became clear to me that the setting of the light switch had something to do with the voltage.
• • A-B-C: test carried out with the car parked and on idle, light switch on: voltage drops to 14.3V on first attempt, on the two next attempt the voltage did not go up to 14.7V but stayed at 14.3V
  • D: also at idle, but now I turned the light switch to park and noticed that the voltage immediately dropped to 12.7V
  • E: went for a 10 min drive
  • F: stopped the car and started again but now with light switch off. Voltage goes up to only 12.7V. Tried for a few seconds to turn the light switch on and the voltage jumps up to 14.3V
  • G to J: driving back now with the light switch off. Voltage drops from 14.5V to 12.7V after 138 sec, then at point H I switched the light back on for a few seconds. After 5 min the voltage starts to toggle between 12.7V and 13.4V. At point J I get home and the Auto Stop kicks in before I stop the car.

This morning I did a new recording on the way to work, now with light switch off.
The result can be seen as Test 10a.

• As always with switch off the voltage drops from 14.7V to 12.7V after 160sec
• After 10min the voltage starts to toggle between 12.4 and 13.4V
• After another 10 min drive the voltage toggle between 13.6V - 14.2V - 14.7

...next recording on way back from work

[steinrk]

...forgot to add the pictures showing the differences between light on and light off.

[GordonG]

Petrol SLX does it too. Now involved with local dealer (helpful so far) with my car which has blown several globes in two years, but only travelled less than 29,000 km.

After installation of the last set, the alignment of the lighting is so bad I can't see the side of the road properly!

Awaiting a call from the dealer now...

(And yes, I've been missing from this forum for a long time!  )

[Phil №❶]

GordonG

Please Explain !!! - (P. Hanson) 

Can you elaborate on how the dealer is being helpful.

I've posted some info on system voltages after start up & I think there may be some value in investigating it further. 

[GordonG]

Helpful in that they are prepared to listen to me. But I haven't started ranting and raving yet Also spoke to Hyundai and they sent up two new globes FOC that the dealer installed; however they are pointing anywhere but where I need them to be. Nearly ran over a guy I didn't even see night before last! He was in army camo, which didn't help, but still... Missed a call from them yesterday evening (I was teaching at karate) so should get a call today. Maybe when I explain why I missed their call, I'll get some prompt attention 

[Surferdude]

. Missed a call from them yesterday evening (I was teaching at karate) so should get a call today. Maybe when I explain why I missed their call, I'll get some prompt attention 

 

[neoto]

@steinrk: I have a 2011 Czech-made diesel i30cw. The dashboard you have is called Supervision here in Slovenia and is almost impossible to get (I have dials for gas tank and engine temperature, not LCD display). Anyway, in Slovenia it is also mandatory to have the lights on all the time and therefore, lights turn on automatically as in your case. But there is a difference in dashboard illumination between your car and mine - when the lights switch is off, only the trip computer, radio and A/C displays are maximally lit, anything else is in darkness (all the dials, buttons, ... are off).

Can you check whether the voltage on the battery and the voltage reported by the ECU over OBD-II is the same? I will try to hook up a OBD-II dongle and monitor voltages, but not before the end of the week.

I have my i30 for 7 months now and have done nearly 28k km. I drive with both light swich settings (I must turn the lights switched off to see anything on the trip computer display during the day and I must have lights switched on during the night to not be blinded by the maximum illuminated displays).
I haven't experienced any headlights blows.... yet.

[accim]

@steinrk: I have a 2011 Czech-made diesel i30cw. The dashboard you have is called Supervision here in Slovenia and is almost impossible to get (I have dials for gas tank and engine temperature, not LCD display). Anyway, in Slovenia it is also mandatory to have the lights on all the time and therefore, lights turn on automatically as in your case. But there is a difference in dashboard illumination between your car and mine - when the lights switch is off, only the trip computer, radio and A/C displays are maximally lit, anything else is in darkness (all the dials, buttons, ... are off).

Can you check whether the voltage on the battery and the voltage reported by the ECU over OBD-II is the same? I will try to hook up a OBD-II dongle and monitor voltages, but not before the end of the week.

I have my i30 for 7 months now and have done nearly 28k km. I drive with both light swich settings (I must turn the lights switched off to see anything on the trip computer display during the day and I must have lights switched on during the night to not be blinded by the maximum illuminated displays).
I haven't experienced any headlights blows.... yet.

As you know, there is a user Lynx (Hyundai-klub Slovenia), that might help you with OBD-II and that stuff. I don't know exactly what you have or don't have nor what he has or doesn't have, heck I don't even know what exactly you need, but in case you forgot, you could check with him. He is also from Celje anway.. 

[neoto]

I have this one: http://www.dealextreme.com/p/obdii-bluetooth-car-diagnostic-cable-black-blue-orange-dc-12v-42825.