Charging Test ... Excessive Ripple

[JAS21]

So my AAB picked up our MY15 Everest from Ford Service earlier today.

 

They didn’t mention to her that the results from the Midtronics indicated Excessive Ripple. I have never seen that printed on any of the test sheets from the previous five years plus of service.

 

I have a Fluke and confirmed that it does block DC when selected to AC.

 

So I ran the engine at about 1500rpm with the headlights on and measured the AC voltage across the battery …. I got basically nothing  (0.008V)… I understand, I hope, from reading that 0.1V AC could indicate a diode fault.

 

So it appears, to me, that there is not a problem. But I certainly don’t want trouble to develop associated  with the Can bus or any of the ECUs as it is now out of warranty.

 

Anyone got any views on the above? Am I testing this correctly? Should I be at all concerned? 

 

I changed the battery when it was just less than four years old. It wasn’t giving problems but at that age …I didn’t want to get a call saying it won’t start 'help me'....

 

Actually that battery voltage dropped a bit on starting and it had my CTEK on all night.  

[Crossy]

They've not even bothered to set up their Midtronics unit with their name etc.

I wonder when it was last calibrated.

 

Interesting that there's no actual value (and no test limits) associated with the "excessive" ripple.

 

I would imagine that a failed diode in the rectifier pack would be giving nearer a volt of ripple and/or a lower DC charge voltage.

 

If worried take to beast to another outlet with a different tester and see what they say.

 

To be honest I suggest "you think too mutt".

 

EDIT: The manual for the MDX-700 (couldn't find the 300) is emphatic that "excessive ripple" is a failed diode pack or damaged stator, but your measurements don't support this.

 

[KhaoYai]

Ex Mechanic but pre can bus - however, a simple voltmeter test across your battery terminals should produce 12v + with the engine off and anywhere between 13.5v and 14.5v running at 1000rpm+.  Some regulators don't open until around 900rpm but I've never known one that opens much later than 1000rpm unless its faulty.

 

The charging test on the printout is showing 14.18v and that's fine.  I'd be happier with closer to 14.5v but the rpm for that test is not stated so it might not be the max charge.

 

A battery voltage test should be carried out with all equipment switched off.

 

I suspect that the test equipment they haver used would state 'Excessive Ripple' on most vehicles - I doubt its true.

 

To be honest, apart from fluctuations in the charge rate, I don't know what they mean by 'Excessive Ripple'.

 

You could try changing the alternator but I suspect you'll get the same result.

 

I think you have either connected your volt meter incorrectly or its faulty - if the voltage you achieved was a correct reading, your car wouldn't be starting by now.

 

Can I ask, what prompted the Midtronics test?  Is it something they offer as part of their service routine or did you report a fault?  If it is part of their routine, put it in the bin and forget about it - its almost certainly a sales gimmick and will most likely find 'faults' on most cars.

[KhaoYai]

As a general pointer to others reading this - be extremely carefull with the electrical systems on modern cars. Basically don't touch them unless you have knowledge.

 

Auto electrics have always been a law unto themselves - quite a few 'normal' electricians don't understand them but on today's vehicles they really are complex beasts and can cost 0000's when they go wrong. 

 

Things are not how they used to be - simply jump starting can cause quite severe damage to one or more of the many modules in the electrics.

 

Just changing a battery can require a 'procedure' before starting the vehicle to reset one or more of the same modules.  Always consult you vehicle's handbook to check on that and if in doubt, leave well alone.  An example - (even I get caught out by this modern cr ap) I changed the battery on my van recently and the indicators wouldn't run. I eventually found out that I hadn't carried out the reset procedure for the body control module when I refitted the battery following a repair.  I had to disconnect it again for 10 minutes and then carry out the reset procedure.  I had no idea that I couldn't simply fit a new battery and go.

 

If you are unlucky enough to encounter a serious electrical fault on your vehicle - find a real auto electrics specialist.  I very much doubt that many of the 'main dealers' in Thai garages have technicians with the knowledge to test and repair these extremely complex systems.

 

Unless you know its safe, I would recommend you don't carry out any 'home testing' on modern cars. Leave well alone.

[KhaoYai]

35 minutes ago, Crossy said:

They've not even bothered to set up their Midtronics unit with their name etc

What's your betting they don't know how?

[Crossy]

1 minute ago, KhaoYai said:

What's your betting they don't know how?

 

RTFM methinks.

[tifino]

I find a good practical upper limit on touching the electrics

- is to temporarily parallel-connect another battery to maintain the 12V whilst removing/replacing the actual car battery... 

 

 

aren't we glad that Apple doesn't make cars!!

 - they'd Serialise the battery to the car fer sure...

[teacherclaire]

55 minutes ago, KhaoYai said:

Ex Mechanic but pre can bus - however, a simple voltmeter test across your battery terminals should produce 12v + with the engine off and anywhere between 13.5v and 14.5v running at 1000rpm+.  Some regulators don't open until around 900rpm but I've never known one that opens much later than 1000rpm unless its faulty.

 

The charging test on the printout is showing 14.18v and that's fine.  I'd be happier with closer to 14.5v but the rpm for that test is not stated so it might not be the max charge.

 

A battery voltage test should be carried out with all equipment switched off.

 

I suspect that the test equipment they haver used would state 'Excessive Ripple' on most vehicles - I doubt its true.

 

To be honest, apart from fluctuations in the charge rate, I don't know what they mean by 'Excessive Ripple'.

 

You could try changing the alternator but I suspect you'll get the same result.

 

I think you have either connected your volt meter incorrectly or its faulty - if the voltage you achieved was a correct reading, your car wouldn't be starting by now.

 

Can I ask, what prompted the Midtronics test?  Is it something they offer as part of their service routine or did you report a fault?  If it is part of their routine, put it in the bin and forget about it - its almost certainly a sales gimmick and will most likely find 'faults' on most cars.

The charging test on the printout is showing 14.18v and that's fine.  I'd be happier with closer to 14.5v but the rpm for that test is not stated so it might not be the max charge.

 

Not necessarily true. Some regulators/rectifiers stop at 13.8 volts depending on vehicle/alternator, of course. 

[tifino]

5 minutes ago, teacherclaire said:

The charging test on the printout is showing 14.18v and that's fine.  I'd be happier with closer to 14.5v but the rpm for that test is not stated so it might not be the max charge.

 

Not necessarily true. Some regulators/rectifiers stop at 13.8 volts depending on vehicle/alternator, of course. 

that 13.8v vs a higher voltage comes from whether the vehicle is set up for a Battery you can top up; or one designed to run higher voltage for closer compatability with maintenance-free aka throwaway battery set up... 

[JAS21]

1 hour ago, Crossy said:

They've not even bothered to set up their Midtronics unit with their name etc.

I wonder when it was last calibrated.

 

Interesting that there's no actual value (and no test limits) associated with the "excessive" ripple.

 

I would imagine that a failed diode in the rectifier pack would be giving nearer a volt of ripple and/or a lower DC charge voltage.

 

If worried take to beast to another outlet with a different tester and see what they say.

 

To be honest I suggest "you think too mutt".

 

EDIT: The manual for the MDX-700 (couldn't find the 300) is emphatic that "excessive ripple" is a failed diode pack or damaged stator, but your measurements don't support this.

 

I don't think I have ever seen one set up with all the info. The Midtronics tester is used by many dealerships. Yes. that's the problem, I know it means a failed diode, I'm just slightly concerned that my Fluke is not accurate at low values. Good idea to stick it on someone else's unit. Only real way of course is a 'scope' and look at the waveform.  'll try and find an auto election .. a good one. 

 

Tomorrow I'll stick my Fluke on the other car and see what it reads. 

[JAS21]

1 hour ago, KhaoYai said:

Ex Mechanic but pre can bus - however, a simple voltmeter test across your battery terminals should produce 12v + with the engine off and anywhere between 13.5v and 14.5v running at 1000rpm+.  Some regulators don't open until around 900rpm but I've never known one that opens much later than 1000rpm unless its faulty.

 

The charging test on the printout is showing 14.18v and that's fine.  I'd be happier with closer to 14.5v but the rpm for that test is not stated so it might not be the max charge.

 

A battery voltage test should be carried out with all equipment switched off.

 

I suspect that the test equipment they haver used would state 'Excessive Ripple' on most vehicles - I doubt its true.

 

To be honest, apart from fluctuations in the charge rate,

 

 

You could try changing the alternator but I suspect you'll get the same result.

 

I think you have either connected your volt meter incorrectly or its faulty - if the voltage you achieved was a correct reading, your car wouldn't be starting by now.

 

Can I ask, what prompted the Midtronics test?  Is it something they offer as part of their service routine or did you report a fault?  If it is part of their routine, put it in the bin and forget about it - its almost certainly a sales gimmick and will most likely find 'faults' on most cars.

I suspect that the test equipment they haver used would state 'Excessive Ripple' on most vehicles - I doubt its true. It is a very common piece of equipment, quick and easy to use, I have many of those bits of paper and never have I seen Excessive Ripple.

 

I don't know what they mean by 'Excessive Ripple'. I realise that.

 

I think you have either connected your volt meter incorrectly or its faulty - if the voltage you achieved was a correct reading, your car wouldn't be starting by now. There is a subtle difference between ac and dc ????

 

Midtronics test .... I know for a fact that Mercedes, Honda and Ford use it.

[KhaoYai]

1 hour ago, teacherclaire said:

Not necessarily true. Some regulators/rectifiers stop at 13.8 volts depending on vehicle/alternator, of course.

Which part is not true?  I said 'I'd be happier' and you might note earlier I stated 'anywhere between 13.5v and 14.5v running at 1000rpm+'.

 

No disrespect but you're a teacher, I spent most of my working life in the motor trade.

 

 

[KhaoYai]

11 minutes ago, JAS21 said:

I think you have either connected your volt meter incorrectly or its faulty - if the voltage you achieved was a correct reading, your car wouldn't be starting by now. There is a subtle difference between ac and dc 

Ah, you made the understandable mistake of setting it to AC because you were testing alternator output? That would explain your readings.

 

Thinking about the 'Excessive Ripple' thing, I'd take a stab it means fluctuation in current.  That can be a sign that an alternator is on its way out - regulator cutting in and out.  Having said that, my van's had a similar 'fault' for 30,000 miles - it shows as a slight flicker in the headlamps between 1500 - 2000rpm.  I have no plans to change the alternator.

[KhaoYai]

1 hour ago, tifino said:

aren't we glad that Apple doesn't make cars!!

 - they'd Serialise the battery to the car fer sure...

That is here already - or something similar. BMW et al now require new batteries to be registered on some occasions.

 

Guess what - you have to pay for the registration!

[KhaoYai]

19 minutes ago, JAS21 said:

Midtronics test .... I know for a fact that Mercedes, Honda and Ford use it.

I don't doubt it - no doubt its a good little earner.  All of those dealers have their own diagnostic equipment that I'd suggest gives far more information than the Midtronics system does.

 

Note: The P300 appears to be Midtronics 'entry level' tester costing around 12,000 baht. Dealer diagnostics start at around 600,000 - why would a dealer want a Midtronics tester?

[JAS21]

28 minutes ago, KhaoYai said:

I don't doubt it - no doubt its a good little earner.  All of those dealers have their own diagnostic equipment that I'd suggest gives far more information than the Midtronics system does.

 

Note: The P300 appears to be Midtronics 'entry level' tester costing around 12,000 baht. Dealer diagnostics start at around 600,000 - why would a dealer want a Midtronics tester?

I agree with you ......

[Crossy]

10 hours ago, KhaoYai said:

Ah, you made the understandable mistake of setting it to AC because you were testing alternator output? That would explain your readings.

 

His Fluke will measure AC superimposed on DC (that's what "ripple" is) and should read the AC component only.

 

That said, 8mV does seem small, very close to the limit of the meter  @JAS21 what does it read when the engine isn't running?

[KhaoYai]

18 minutes ago, Crossy said:

His Fluke will measure AC superimposed on DC (that's what "ripple" is) and should read the AC component only.

Thanks for the explanation - Ripple is not a term I've heard in the UK - possibly a US term?

 

No idea what a Fluke is, For what I need these days, I use a standard voltmeter and when its set to AC it gives a similar reading (from memory) when testing a car's output - DC works fine.

 

Right now I'm wishing I could find a good auto sparks here in the UK that charges £1 per hour ????.  My daughter's car has a mystery battery drain - hard enough to find in my day when circuit isolation was first base with such faults but in these days of multiple can-bus circuits running multiple control modules?  A daunting task.

 

In the past I'd say that on 60% of the vehicles I came across with a battery drain, the alternator turned out to be the culpit - they appeared fine when running but were sending a low current to earth when stationary. As soon as the weather here improves, I'll leave it disconnected one night and see what happens.  Failing that, she can live with it or pay a sparky - I cringe just trying to read the wiring diagram.

[Crossy]

11 minutes ago, KhaoYai said:

Thanks for the explanation - Ripple is not a term I've heard in the UK - possibly a US term?

 

No idea what a Fluke is, For what I need these days, I use a standard voltmeter and when its set to AC it gives a similar reading (from memory) when testing a car's output - DC works fine.

 

Brit here, "Ripple" is a standard electrical/electronic engineering term. Except when your (my) poor handwriting gets interpreted by the typist and included in 100 page report as "the power supply has excessive nipple". It was missed by the proof reader and a large number of copies printed and distributed. Only one person noticed!

 

"Fluke" is a well known test equipment manufacturer who generally specialise in test meters, refering to a "Fluke" generally means a high-quality digital multimeter. 

 

Many, many of us cut our teeth on a Fluke 75 of one generation or another.

 

[KhaoYai]

2 minutes ago, Crossy said:

"Fluke" is a well known test equipment manufacturer who generally specilaised in test meters, refering to "a Fluke" generally means a high-quality digital multimeter. 

I can't speak for modern auto electrics but 'Fluke' is not a term I've ever heard in the automotive field or from an auto sparks. Mind you, they were always mysterious creatures that couldn't understand why mechanics had no idea what they were talking about.  Good ones are very much in demand these days and increasingly so.

[Crossy]

5 minutes ago, KhaoYai said:

I can't speak for modern auto electrics but 'Fluke' is not a term I've ever heard in the automotive field or from an auto sparks. 

 

Yeah, automotive test kit is far too specialist for a company like Fluke. They do make an "Automotive multimeter" but generally concentrate on general electrical/electronic engineering tools.  

[canthai55]

https://www.fluke.com/en-th

[OneMoreFarang]

14 hours ago, JAS21 said:

So I ran the engine at about 1500rpm with the headlights on and measured the AC voltage across the battery …. I got basically nothing  (0.008V)… I understand, I hope, from reading that 0.1V AC could indicate a diode fault.

When you measure voltage across the battery you won't measure much AC because the battery is like a huge capacitor which more or less shortcuts AC. Try measuring it as near as possible to the generator and you will have a higher value. I don't know how much ripple is normal for cars.

14 hours ago, JAS21 said:

So it appears, to me, that there is not a problem. But I certainly don’t want trouble to develop associated  with the Can bus or any of the ECUs as it is now out of warranty.

Don't worry about the CAN bus and the ECUs. Car electronics is build very robust, i.e. it has to survive double the nominal voltage so even connecting 24V won't kill car electronics. And the ECUs and any CAN device will have their own voltage regulators and filters. They will filter out any excessive ripple if it exists.

 

In general about electronics in cars: Looking in any electronic shop (i.e. DigiKey) many parts are available for different standards. Military is the highest standard and right below that is automotive. Here is some more info if you care:

Automotive Grade Quality Products (AEC-Q100 and... | element14 | Transportation | Automotive Electronics

[OneMoreFarang]

43 minutes ago, KhaoYai said:

I can't speak for modern auto electrics but 'Fluke' is not a term I've ever heard in the automotive field or from an auto sparks. Mind you, they were always mysterious creatures that couldn't understand why mechanics had no idea what they were talking about.  Good ones are very much in demand these days and increasingly so.

Fluke is worldwide knows as top of the range equipment with top of the range prices.

I just checked. Their "best value" digital multimeter cost only 225 USD.

Many professionals buy Fluke.

[JAS21]

Thanks OMF and Crossy. My background is heavy electric, 11kV generators, 275kV and 400kV systems, so I don’t understand too much about this mV stuff … it’s not proper electric anyway is it.

 

On modern cars it’s not easy to get your probes onto the alternator output terminals. Ford use a ‘smart charge system’ and maybe I put my probes in the wrong place anyway. There is another connection on the +ve terminal with a ‘thingie’ between it and the battery.

 

So later today I’ll get AAB to help me re-test, and also this time I’ll load the alternator as much as I can.

 

The Everest will actually run without a battery (after it has been started of course) but it won’t run for long without an alternator. As I try to keep her out of the seat, which has a steering wheel nearby, in my car, she tends to use the SUV ‘thankfully’ and I don’t want her stranded somewhere.  I need to decide if there is a problem or not.

 

I’ll post a pic of Fluke readings, before testing and during later. ..... I think the only real way to sort this is using a scope but I guess not easy to find someone with one here and who can actually use it ....

[ExpatOilWorker]

4 minutes ago, JAS21 said:

Thanks OMF and Crossy. My background is heavy electric, 11kV generators, 275kV and 400kV systems, so I don’t understand too much about this mV stuff … it’s not proper electric anyway is it.

 

On modern cars it’s not easy to get your probes onto the alternator output terminals. Ford use a ‘smart charge system’ and maybe I put my probes in the wrong place anyway. There is another connection on the +ve terminal with a ‘thingie’ between it and the battery.

 

So later today I’ll get AAB to help me re-test, and also this time I’ll load the alternator as much as I can.

 

The Everest will actually run without a battery (after it has been started of course) but it won’t run for long without an alternator. As I try to keep her out of the seat, which has a steering wheel nearby, in my car, she tends to use the SUV ‘thankfully’ and I don’t want her stranded somewhere.  I need to decide if there is a problem or not.

 

I’ll post a pic of Fluke readings, before testing and during later. .....

400 kV, wow. 

I don't mean to hijack your thread, but just want to share a few pictures from a condo in Bangkok. 

Back to ripple testing.

 

[JAS21]

3 minutes ago, ExpatOilWorker said:

400 kV, wow. 

I don't mean to hijack your thread, but just want to share a few pictures from a condo in Bangkok. 

Back to ripple testing.

 

That is just extra insulation ......

[JAS21]

3 hours ago, JAS21 said:

Thanks OMF and Crossy. My background is heavy electric, 11kV generators, 275kV and 400kV systems, so I don’t understand too much about this mV stuff … it’s not proper electric anyway is it.

 

On modern cars it’s not easy to get your probes onto the alternator output terminals. Ford use a ‘smart charge system’ and maybe I put my probes in the wrong place anyway. There is another connection on the +ve terminal with a ‘thingie’ between it and the battery.

 

So later today I’ll get AAB to help me re-test, and also this time I’ll load the alternator as much as I can.

 

The Everest will actually run without a battery (after it has been started of course) but it won’t run for long without an alternator. As I try to keep her out of the seat, which has a steering wheel nearby, in my car, she tends to use the SUV ‘thankfully’ and I don’t want her stranded somewhere.  I need to decide if there is a problem or not.

 

I’ll post a pic of Fluke readings, before testing and during later. ..... I think the only real way to sort this is using a scope but I guess not easy to find someone with one here and who can actually use it ....

 

So as Crossy suggested my meter on open circuit reading was  0.003V

 

Proving meter completely blocked DC

 

AC reading across battery 1500rpm and alternator loaded.

 

So I don't see a problem. I'll ask AAB to phone the dealership tomorrow and see what they have to say as they would have only stuck their meter across the battery.

[quake]

if it ain't broke, don't fix it. 

[VocalNeal]

4 hours ago, KhaoYai said:

My daughter's car has a mystery battery drain

 

Mercedes? I know two guys with Sprinters who had mystery drains. Stop and won't start. leave for a while...might. Next day fine. 

 

Can't remember the actual fix. but could find out.