Mazda 6 doesn't like Canadian winters

[Elektrishun]

That's a good general overview, however, he's in a warm shop and that engine is cranking like crazy. So his values are different than what you'd see in a cold climate, no crank situation. His statement about different allowable values for the positive and negative side is incorrect in my opinion. Ideally they would be the same and less than 0.5v. In colder weather, higher amp draw during cranking, you'll see slightly higher voltage drops.

I see at the end he used a thermal camera. Thats my go to when i have a no crank with a battery above 12.5v. You'll usually see the problem as fast as he shows it.

There is definitely some different approaches to this test.
I watched a couple of this guy's videos, too:

 

[PeterT]

His statement about different allowable values for the positive and negative side is incorrect in my opinion. Ideally they would be the same and less than 0.5v.

Q1, I get how he is proceeding down the line on the negative side, but is measuring voltage drop any different than measuring resistance? (~8:55)..

Q2, maybe I'm visualizing this wrong. When you measure voltage between battery & motor (B-terminal or whatever) you get a drop that should be within some recommended range. But now you have an unhealthy battery which I take to mean both a reduced voltage &/or it suppresses at a faster slope. So you do the same test, presumably read a higher drop for that reason, but aren't you chasing the wrong culprit? ie. its a battery issue not a wiring/motor side issue?

Q3, can you elaborate on the thermal imaging thing. What is it indicating?

 

[Susquatch]

There is definitely some different approaches to this test.
I watched a couple of this guy's videos, too:

Sorry for being MIA here too much. I've got a bad cold and I am bedridden.

As most members know, I am no fan of UTube. The guy in your video makes a shit load of assumptions about what his viewers know and don't know. He also said a few things that made me question what he really knows.

I think you missed Darren's point. I believe his point is that you cannot reliably replicate a low temperature electrical connection problem in a heated garage. Temperature can have a dramatic impact on connection integrity. When we talk about testing drops at various connections, low temperature (and high temperature) can expand/contract/loosen/tighten, and even disconnect otherwise good connections.

I spent my career designing and developing vehicles and i have spent a significant amount of time in Thompson Manitoba doing low temperature testing. Darren's comments are bang on and you would do well to follow his advice.

My own advice is to watch YouTube a little less and to read Darren's advice a little more. For now, I'll avoid complicating what he said.

Please don't take this wrong. Your username is @Elektrishun. That naturally leads me to think that you are an electrician. But maybe not. Can you please qualify yourself with an overview of your electrical knowledge and experience? In particular, how much experience do you have with Low Voltage DC Circuits? Please don't take that negatively. I just think that knowing more about you and your electrical experience helps us all know how to communicate best with you.

but is measuring voltage drop any different than measuring resistance?

Not really. Most resistance measurements are really voltage and current measurements. R=V/I. The nice thing about measuring voltage drops is that you don't have to disconnect the circuit to know a lot about what is going on.

Q3, can you elaborate on the thermal imaging thing. What is it indicating?

Bad connections usually get very hot compared to their surroundings. Thermal imaging is a very easy and very fast way to spot bad connections.

 

[Susquatch]

When I test a battery I usually do two tests; in the vehicle with an Innova OBDII reader and out of the vehicle with a traditional load tester along with a Volt meter to watch the voltage as it drops and recovers.

Unless these tests are insufficient the battery is good.

They are usually good enough for summer testing, but won't be valid in winter. Also, they may fail to show a low capacity battery. Very few load testers draw the kind of power that a starter draws turning over a cold engine.

I'd still like to hear your assessment of the way your cold engine cranks on its own battery vs the way it cranks on a set of a jumper cables to a running vehicle. You have had several back to back, successful and unsuccessful starts. How does the starting rpm compare for each? Basically, I am wanting to see if the cranking speed correlates with successful starting.

The reason for knowing this is to see if the problem might be elsewhere - fuel, ignition, etc.

 

[phaxtris]

I have come across a bad connection/cable from battery to solenoid on more than one occasion, as well as the obvious bad grounds



2.5 ? My wife's 2012 Mazda 5 with 2.5 starts no problem at -30 after sitting for several days, and that's after running her power sliding door, swing our drivers chair and wheel chair lift, battery is a 5 year old optima yellow top

I missed, are you using a resistance battery tester ? Those are so-so....a battery will test good when warm, then -25 comes and it's another story

 

[Elektrishun]

Q1, I get how he is proceeding down the line on the negative side, but is measuring voltage drop any different than measuring resistance? (~8:55)..
View attachment 56259


Q2, maybe I'm visualizing this wrong. When you measure voltage between battery & motor (B-terminal or whatever) you get a drop that should be within some recommended range. But now you have an unhealthy battery which I take to mean both a reduced voltage &/or it suppresses at a faster slope. So you do the same test, presumably read a higher drop for that reason, but aren't you chasing the wrong culprit? ie. its a battery issue not a wiring/motor side issue?
View attachment 56260

Q3, can you elaborate on the thermal imaging thing. What is it indicating?

A voltage drop test requires current flow and will indicate a problem when there is resistance. Resistance will create heat and that's where the thermal imager is useful.
Without current flowing no heat is created at the problem spot in the circuit. Therefore a simple resistance measurement can not readily find what a voltage drop test and thermal imager can.

Sorry for being MIA here too much. I've got a bad cold and I am bedridden.

As most members know, I am no fan of UTube. The guy in your video makes a shit load of assumptions about what his viewers know and don't know. He also said a few things that made me question what he really knows.

I think you missed Darren's point. I believe his point is that you cannot reliably replicate a low temperature electrical connection problem in a heated garage. Temperature can have a dramatic impact on connection integrity. When we talk about testing drops at various connections, low temperature (and high temperature) can expand/contract/loosen/tighten, and even disconnect otherwise good connections.

I spent my career designing and developing vehicles and i have spent a significant amount of time in Thompson Manitoba doing low temperature testing. Darren's comments are bang on and you would do well to follow his advice.

My own advice is to watch YouTube a little less and to read Darren's advice a little more. For now, I'll avoid complicating what he said.

Please don't take this wrong. Your username is @Elektrishun. That naturally leads me to think that you are an electrician. But maybe not. Can you please qualify yourself with an overview of your electrical knowledge and experience? In particular, how much experience do you have with Low Voltage DC Circuits? Please don't take that negatively. I just think that knowing more about you and your electrical experience helps us all know how to communicate best with you.



Not really. Most resistance measurements are really voltage and current measurements. R=V/I. The nice thing about measuring voltage drops is that you don't have to disconnect the circuit to know a lot about what is going on.



Bad connections usually get very hot compared to their surroundings. Thermal imaging is a very easy and very fast way to spot bad connections.

I am a journeyman electrician who worked in both construction and maintenance. Not a mechanic.

I use every available resource I can to solve a problem including YouTube videos. I have never taken advice from one source when trying to solve seemingly difficult problems.
Get a variety of different inputs, look for consistency in the comments, see if it applies to my specific situation, and give it a go.

I understand Darren's advice. But since a voltage drop test, as it applies to a vehicle, is not something I have tried before with starting issues I needed to investigate how the experts go about it. Clearly, not everyone does it the same way. So I need to find what will work best for my specific situation.

For example, I had intermittent starting issues with a 1991 Ford Escort. Drove me nuts because it seemed so random. Chased it for months and asked all kinds of people for opinions, checked YouTube, car forums, etc.
Finally found 1 conversation on a forum somewhere where someone described a similar issue and cleaning a dirty air intake solenoid was the fix.
I told a few people that I may have found the fix to my problem. The replies were that a dirty air intake solenoid would have nothing to do with my car not starting. Cleaned it anyway and never had a problem starting it again.

Willing to listen to everyone's advice but ultimately I have to chose what the best approach is for my specific circumstances.

BTW hope you get over that cold soon!

 

[Elektrishun]

They are usually good enough for summer testing, but won't be valid in winter. Also, they may fail to show a low capacity battery. Very few load testers draw the kind of power that a starter draws turning over a cold engine.

I'd still like to hear your assessment of the way your cold engine cranks on its own battery vs the way it cranks on a set of a jumper cables to a running vehicle. You have had several back to back, successful and unsuccessful starts. How does the starting rpm compare for each? Basically, I am wanting to see if the cranking speed correlates with successful starting.

The reason for knowing this is to see if the problem might be elsewhere - fuel, ignition, etc.

I appreciate the comments. Always looking to expand my knowledge and improve my chances of solving the problem.

Part of the problem is that it is my son's car and when it fails to start I am not always there to see what is going on.
Sometimes he isn't there either because he uses his remote starter. I try to encourage him to manually start it so that he can give me better feed back when it all goes wrong.

 

[Susquatch]

A voltage drop test requires current flow and will indicate a problem when there is resistance. Resistance will create heat and that's where the thermal imager is useful.
Without current flowing no heat is created at the problem spot in the circuit. Therefore a simple resistance measurement can not readily find what a voltage drop test and thermal imager can.

I am a journeyman electrician who worked in both construction and maintenance. Not a mechanic.

I use every available resource I can to solve a problem including YouTube videos. I have never taken advice from one source when trying to solve seemingly difficult problems.
Get a variety of different inputs, look for consistency in the comments, see if it applies to my specific situation, and give it a go.

I understand Darren's advice. But since a voltage drop test, as it applies to a vehicle, is not something I have tried before with starting issues I needed to investigate how the experts go about it. Clearly, not everyone does it the same way. So I need to find what will work best for my specific situation.

For example, I had intermittent starting issues with a 1991 Ford Escort. Drove me nuts because it seemed so random. Chased it for months and asked all kinds of people for opinions, checked YouTube, car forums, etc.
Finally found 1 conversation on a forum somewhere where someone described a similar issue and cleaning a dirty air intake solenoid was the fix.
I told a few people that I may have found the fix to my problem. The replies were that a dirty air intake solenoid would have nothing to do with my car not starting. Cleaned it anyway and never had a problem starting it again.

Willing to listen to everyone's advice but ultimately I have to chose what the best approach is for my specific circumstances.

BTW hope you get over that cold soon!

OK, so you are an electrician. That helps a lot! I gather you don't have a lot of low voltage DC experience though. Which also helps to know.

Your Ford Escort experience is exactly why I want to know what your cranking is like when you get a successful cold start vs an unsuccessful one. There are lots of things that can affect starting at low temperatures. So I'm looking for clues about what affects it and not.

If you get good cranking for both good start and bad start, then it might not be the battery at all.

It's easy to assume the battery and electrical connections are at fault when it's -30 out. That because it usually is. So naturally, that's where all of us go first.

I'm just casting in the Lilly Pads here to evaluate odds.

Nonetheless, the odds are very high that your problem is a bad battery or a bad connection. So that's where your focus should be.

Now if you tell me that it cranks the same for both successful and unsuccessful cold starts, those odds suddenly change.

 

[Tom O]

A friend of mine once had a battery that seamed dead but it was the corrosion on the terminals so after a proper cleaning it worked perfectly.

 

[Elektrishun]

I have come across a bad connection/cable from battery to solenoid on more than one occasion, as well as the obvious bad grounds



2.5 ? My wife's 2012 Mazda 5 with 2.5 starts no problem at -30 after sitting for several days, and that's after running her power sliding door, swing our drivers chair and wheel chair lift, battery is a 5 year old optima yellow top

I missed, are you using a resistance battery tester ? Those are so-so....a battery will test good when warm, then -25 comes and it's another story

I have used a resistance battery tester and a test with a Innova OBDII tester. The Innova has a test for both the battery and alternator.

 

[Susquatch]

Part of the problem is that it is my son's car and when it fails to start I am not always there to see what is going on.
Sometimes he isn't there either because he uses his remote starter. I try to encourage him to manually start it so that he can give me better feed back when it all goes wrong.

Ain't it the truth!

Now picture us trying to help you one level removed.....

Been there, done that.

Ya, tell him if he doesn't start it manually he is on his own...... That's what I would tell my kids and their kids.

 

[Susquatch]

I have used a resistance battery tester and a test with a Innova OBDII tester. The Innova has a test for both the battery and alternator.

I believe (but could be wrong) that the Innova doesn't really test the battery itself at all. It merely asks the onboard computer to tell it what its battery and alternator evaluations were. But I retired 20 years ago so things may have changed.

Resistance testing of a battery is a good way to evaluate it, but it's not perfect.

 

[Susquatch]

I understand Darren's advice. But since a voltage drop test, as it applies to a vehicle, is not something I have tried before with starting issues I needed to investigate how the experts go about it. Clearly, not everyone does it the same way. So I need to find what will work best for my specific situation.

Trust me on this one. Darren knows what he is talking about.

That said, your approach to evaluating advice is similar to my own.

Setting everything everyone may have told you aside, Fundamentally, voltage drop testing is all about evaluating connections. Your description earlier is perfect.

 

[Elektrishun]

OK, so you are an electrician. That helps a lot! I gather you don't have a lot of low voltage DC experience though. Which also helps to know.

Your Ford Escort experience is exactly why I want to know what your cranking is like when you get a successful cold start vs an unsuccessful one. There are lots of things that can affect starting at low temperatures. So I'm looking for clues about what affects it and not.

If you get good cranking for both good start and bad start, then it might not be the battery at all.

It's easy to assume the battery and electrical connections are at fault when it's -30 out. That because it usually is. So naturally, that's where all of us go first.

I'm just casting in the Lilly Pads here to evaluate odds.

Nonetheless, the odds are very high that your problem is a bad battery or a bad connection. So that's where your focus should be.

Now if you tell me that it cranks the same for both successful and unsuccessful cold starts, those odds suddenly change.

Well, from the sounds of it, relative to your background, I do not have a lot of low voltage DC experience. I have built some various circuits including a couple of variable DC power supplies, RF test equipment such as a DDS VFO and RF power sampler, and recently I built a low powered FM transmitter.
Pretty sure I will be asking you for some electronics advice in the future.

 

[Elektrishun]

Ain't it the truth!

Now picture us trying to help you one level removed.....

Been there, done that.

Ya, tell him if he doesn't start it manually he is on his own...... That's what I would tell my kids and their kids.

I don't get mad often and I have great relationships with all of my family but when he said he tried starting his car with the remote after telling him not to...well ****!

 

[Susquatch]

Well, from the sounds of it, relative to your background, I do not have a lot of low voltage DC experience. I have built some various circuits including a couple of variable DC power supplies, RF test equipment such as a DDS VFO and RF power sampler, and recently I built a low powered FM transmitter.
Pretty sure I will be asking you for some electronics advice in the future.

Well done - so you do have lots of low voltage DC experience! LOL!

Just not car starting at low temperature!

So you know, there is an army of guys on here with experience and knowledge at all levels.

When my kids have problems like your kids, we trade vehicles for a while. That way I can get to the bottom of things quickly.

 

[Elektrishun]

I believe (but could be wrong) that the Innova doesn't really test the battery itself at all. It merely asks the onboard computer to tell it what its battery and alternator evaluations were. But I retired 20 years ago so things may have changed.

Resistance testing of a battery is a good way to evaluate it, but it's not perfect.

You are probably correct. I think this test falls into the category of what many describe as "quick and dirty". Sometimes it can get you pointed in the right direction or lead you on a wild goose chase.
So if in doubt I move on to the load test with DMM connected to watch the voltage.

 

[Darren]

Everything has been covered pretty well here, but @PeterT had a question about resistance tests. They are a valid test, but only when they have too much. Say you test from center of battery negative to engine block, or some other normally grounded point, and your meter reads 5 ohms. That fails under any condition, loaded or not. There is an obvious problem. It should always be very close to zero ohms. The problem is, what if it measures zero ohms in a nice warm shop.....do you assume everything is good? Some people would, but a voltage drop test is the test which will show the problem. One strand of wire will show zero ohms, but cannot pass enough current to crank an engine. It will get hot. The same thing happens with a corroded or loose ground. It can be making clean contact for 10% of its surface, and pass all other tests, except for a voltage drop test under a load of several hundred amps.

 

[Elektrishun]

Well done - so you do have lots of low voltage DC experience! LOL!

Just not car starting at low temperature!

So you know, there is an army of guys on here with experience and knowledge at all levels.

When my kids have problems like your kids, we trade vehicles for a while. That way I can get to the bottom of things quickly.

Exactly. Building circuits that other people have proven to work. I mean, without formal training or some prodigious natural ability, most of us are just splashing in the pool and calling it swimming.
That's why I say I play at mechanics...

 

[Darren]

Yesterday, I was diagnosing a 4wd shift motor. Its controlled by 2 relays that switch polarity to make the motor run one direction or the other to shift the transfer case. First test was to see if the motor was getting power and ground when commanded to shift. Yup, it did, full battery voltage. So I knew the switch and all other controls were working. Bad shift motor right? I then used a 8 amp headlight bulb to load the circuit, and it barely glowed. Replaced the relays and it lit right up.. Bad contacts in the relays. But they passed all other tests until a real load was put on them. Same idea as a car that cranks slow.