2023 Mazda CX-5
11,000 miles
≈14 months old

My car battery is constantly dying. I performed a parasitic draw test, or I attempted to. I turned off the headlights, closed all the doors, put the key fob inside the house, and waited 30 minutes. I ended up getting a reading of 5A on my multimeter. When I tried again, I ended up burning out my multimeter.

I thought I may have touched the positive and negative terminal together by mistake. Bought a new multimeter. The same thing happened. Got a reading of 4.5A but the multimeter burned out again. Something is draining the battery. And something else suddenly turns on that pushes the amperage over 10A, the max on my basic multimeter.

Btw, my driving habits decreased remarkably in the past month. Nowadays, I'm driving once every 2-3 days where the distance isn't very far. I'm assuming that the battery didn't die earlier because my driving recharged the battery. But with less driving, the parasitic draw is finally depleting the battery. And the battery is now not in the best shape. (My multimeter would read .5 voltage drops when turning something on such as headlights or other accessories while the engine is off.)

This is probably irrelevant, but I'd like to add that I got into a small fender bender about 1-2 months ago. The shop replaced the hood, fender, radiator support, and headlights. They insist that the work would not affect the battery. They said that they didn't touch any of the grounds or anything else because they are in the bumper. I'm also thinking a loose ground wouldn't cause a draw.

1. The Hood

Although I closed all the doors, I didn't actuate the hood latch. Do I have to? Does it have a sensor that might be keeping the electronics on?

2. Possible Causes

Any ideas on what might be drawing 5A on a newish CX-5?

By the way, I have been having issues with my keyless remote entry since the first day of purchase. The doors do not lock about a third of the time. Perhaps, something is keeping the computer one, which prevents the doors from locking as well as drains the battery.

3. Clamp Meter

Should I get a clamp meter to figure out where the parasitic draw is coming from?

I was thinking about taking it to the dealer since this is under warranty but they've strongly implied that the work isn't going to be covered. (Yes, extremely shady. I know.) They claim that the earlier bodywork is causing all of this. I don't think it is but the dealer can't get Mazda corporate to pay and they won't do it on their dime. They've implied that it's going to cost $500 just to diagnose it plus more to fix it.

 

Had you taken your vehicle to the dealer and documented your keyless remote issue you might have been able to claim a warranty issue now.
Unfortunately, a fender bender can easily cause the electrical issues you are seeing, which is why the dealer is implying it will not be covered.
Nothing shady here except perhaps the body shop.
As the replacements they did definitely impact wiring and wiring connections can also be easily damaged by incorrect replacement/assembly of said parts.
If it were me, I'd take it to the dealer and get it repaired (you may also need a software update/reset).
If it turns out to be the fault of the body shop, then you can go back and seek a refund/payment for that amount from them.
Otherwise, you will continue to have a vehicle that is not reliable.

Consider that a lesson learned the hard way.
Good luck in whichever way you go.

 

Your Mazda is under WARRATY. Doing any electrical service as a DIY may void many aspects of your warranty if you continue.

Insinuation is not fact, and I would love to see in writing from the Mazda dealership that implied what you are saying they said having to do with the warranty ?

Because your Mazda is under warranty and if you did not add yourself or outside the dealership any electrical parts or upgrades not from Mazda you should be covered under the warranty.

I strongly suggest that you at least go to the dealership and have this concern logged in the service department which will be attach to your VIN history. Ask specific questions concerning your issue and that you should emphasize about the warranty. If all your question was my any other method, then physically being present then it is possible you were told a generic answer about warranty coverage and possibly not covered. Nothing wrong with that mainly because they do not physically have the Mazda there and can't assume every condition or circumstances of the issue. They will need to at least physically check your Mazda and should not charge you for that service concern you have. But read everything every word and how it is worded before you ok the dealership service department to have you Mazda looked at.

I STRONGLY advise not to mention what you have done as a DIY to resolve the issue. STRONGLY!!!!!!! Simply tell them the fact that your battery is depleting and needing to have the battery charged or jump started. Nothing more!!!!!!

If you were my customer and told me what you posted in the first response you made i would have added it either exactly your words or summarized it had you initial, it and then sign the standard work order !!!

I will wait until I get clarification?However it it was independent then it will not be covered under the Mazda warranty
Sooooo about the only thing I did not make a comment on was the BODY damage? You did not state if it was the dealership or independent body shop?

 

I actually took the car to 2 different dealerships because of the keyless remote issue. I posted about this issue on Reddit and another Mazda forum a month after I got the car. Both dealership managers maintained that there was nothing wrong with key fobs. One manager still maintained that even though the doors remain unlocked right in front of him. The tech that was standing there later quietly explained to me that Mazda was refusing to reimburse the dealership for this issue. There is actually no way to input it into Mazda's computer system. As a result, the dealership isn't going to fix a known problem. The tech said that he didn't have many but he had a few people complain about this before. This was about 12 months ago. The problem persists today. It's pretty frustrating.

I got the same reaction over this battery issue. The manager at the dealership admitted that there was something wrong but "he's fairly certain" that it was the auto body shop's fault. He's seen this too many times. I do agree with you that it could be the body shop but I think it's a bit of a stretch to claim he's certain that it's the body shop. He already took $200 for just diagnosing the car. He claimed the car was fine because the battery test came out fine and I could take it home. They obviously thought that the car battery's dying was just in my head. I had to mention to him that the car had died while their valet took it into the garage. When I mentioned that there was some front work done, that's when he claimed the problem must be from that. As a result, I need to pay for all of the work out of my own pocket. It's going to cost me an additional $500 for them to do an additional diagnosis plus more $$ to fix the problem. They said this even though the car is under warranty.

You said it could easily be from the fender bender. The shop owner claims that he didn't touch any of the wires. The dealer argues that he's seen paint mist get onto ground wires and cause issues. But the shop says that he didn't touch the fender where the wires are located. And it's unlikely paint mist would affect any live wires because they're not exposed like that. They're all insulated. I don't know who to believe but the shop seems to make more sense.

What makes the dealer's claims less reliable is that I can tell that getting reimbursed from Mazda corporate via the warranty is a hair-pulling process. So they automatically push all of the costs of repair onto the customer knowing full well that it's a warranty issue. This sentiment exudes strongly every time I talk to them. I completely understand their position as they need to get paid but it's pretty disappointing as a customer because they're saying they know there is a valid warranty claim but they won't do anything because Mazda corporate won't acknowledge it.

 

Sorry but hear say and you posting your problem on various on line forums , some of know are full of bad and undocumented with factual information does not help you here. I suspect the other forums as well. Jumping from one source to another to hope you find the answer from mostly DIY to rally to your side is not helping you either.

On all your visit please provide the actual service write ups given to you. You can remove (redact) your personal information.

I want to see exactly what was done and exactly how it was worded on the service write up. I know how to read them correctly and for any technical information as well and how it was written. I write them every day 5 days a week!!!

ASE

 

Thanks for the advice. I'm probably going to take the car to the dealership after I try to isolate the amp draw. When I do, I'll make sure not to mention that I had tried to diagnose any of this myself. I'll just let them know that the car keeps dying.

I just want to try to isolate the problem myself because it'll protect me. If I can document that the draw is from the car's computer instead of something from the front end, I can make sure the dealer won't lie to me about the true cause later. For example, I wouldn't be surprised if they pretend to diagnose the problem and then claim the problem lies in the front end even though it's the computer. That way they won't have to go through Mazda corporate and have me pay for the whole thing.

Although I won't mention it unless it comes down to it, I also know that the federal Magnuson-Moss Warranty Act protects consumers from companies disclaiming warranties if work was done on the car if it didn't have an impact on what is being claimed under the warranty. Of course, this fact may matter very little if Mazda just refuses to pay for the work even though it's illegal. I'd have to sue via small claims and I don't want to go that way. I've done it a few times (which is far too many). It's just too much stress and work even though most companies eventually settle right before the court date.

You asked about the body damage. It was done by an independent body shop. They said that the ground wires are located in the bumper, which they didn't touch. They only touched the fender, radiator, headlights, and hood. The owner seems like a stand-up guy. He's actually willing to take apart everything for free since he says he stands by his work but he believes it's a waste of time because he believes it's very unlikely the cause is from the front end. He did say it's not 100% certain though because anything could have happened.

I realize that I don't need a clamp meter to isolate the draw. I already know it's drawing 5A with an occasional spike over 10A. Instead, I can determine the number of millivolts across each of the fuses using my basic multimeter. I'll do this once I get a new batch of fuses for my multimeter.

I'm wondering if anyone had any ideas where a 5A+ draw was coming from.

 

I understand what you're saying. I'm just trying to get as much info as possible. I learn a lot from them because I'm a novice. Yes, I get pointed in several different directions but it helps me know the different possibilities. For example, it seems to me that if there is an over 10A draw, the computer is likely waking somehow. It's unlikely something minor like the dome lights. I did turn everything off so maybe I'm triggering the car's computer somehow. And maybe this is why my keyless entry isn't working either. Pure speculation. Hopefully, I can figure it out.

 

I can tell you it is NOT the ECU but the BCM cannot be ruled out without testing properly.

All voltage draw can be accommodated for by measuring the circuit properly.
It should not take more than 1 hour from an experienced and certified (current) Automotive Diagnostic Technica to find the parasitic draw of that measurement. It is basic math example 30 under the hood and 30 in the passenger compartment fuse and or relay circuits. 10 seconds second to measure and verify using the electrical schematic what their normal draw is when ignition is off. 45 minutes to know what circuit has the draw and how to remedy the problem. Give or take the BS of driving the car into the bay getting the diagnostic tools needed and filling the begging info of the service note so 1 hour. LOL If my Techs no better to come to me after an hour for diagnostics even electrical if it tools them over an hour! lol
Ask point blank do you have a Mazda factory Trained and certified Mechanic? Or do you employee a currently ASE Certified Automotive Diagnostic Technician? Anything less expects the "we cant find a problem" answer from any service shop you go to!

 

Thanks for the info. That helps a lot. I'll definitely ask for a Mazda factory traina and certified mechanic. And if they employ an ASE certified automotive diagnostic technician. Do you think it's possible that I need an update like the ns016_23?

You sound like you're a pretty competent person. And I suspect that you're in the top 10% among your counterparts at dealerships. I really wish there was someone like you around here. I can tell you that the dealerships around here are fustrating and untrustworthy. When I first brought the car in, they claimed that the car was fine and that I could take it home. He made it seem as if the car dying was something I made up. (He also did an oil change and washed the car when I had told him it was unnecessary. The oil was changed 2 months prior.) It took me 10 minutes to convince him that there was an actual issue with the car. This is even after telling him that the car had died when the valet tried to bring the car into the garage. He claimed that it could just be the weather.

More frustrating is how he's constantly pushes the costs to me even though it's might be a warranty issue. He and every time I go to a Mazda dealer around here, they make it clear that they don't like to go through Mazda corporate because if it doesn't satisfy their strict qualifications, they aren't going to pay. I guess it's not really the dealer's fault but corporate's. But the dealer should at least apologize that Mazda corporate is being so unreasonable. I can see why Reddit is littered with complaints about this specific dealership.

He's nearly outright saying that I should expect to pay $$ because Mazda is probably not going to cover it. He's "fairly certain". To hear that is surprising.

Again, thanks for the advice. It really helps.

 

on a beach that could be if US Florida or CA. lol
I don't spend time on some internet based groups that need the support of same belief systems regarding many aspects of Auto care and service.

Also whom ever was your employee at Mazda dealership he gave you information overload and either did not himself understand the how things work between a dealership and an auto manufacture or was just guessing based on someone else doing the same. But how a dealership works is another subject altogether.
The update you asked about it would not be fair or correct of me to "guess" if you needed it or already had it uploaded? Thats what the service VIN information world show. If not its free and I would have done it just as a courtesy even if it were not a Mazda notification. You could always ask about it next time at Mazda? But word it as if you seem to have gotten a safety recall of sorts about a battery drain issue. That way you don't have to explain where you read about it. lol I need to smile at time constantly when customers bring my service updates and TSBs and they tell me that what they think is wrong with their vehicle. I often smile and say thank but if I do this service, you want, and it does not cure the issue I need to charge you for that service. I can suggest that if you feel you are not being properly taken care of at service level go ask to speak to the service manager. Be polite about it. Do not threaten to go to Mazda crop because that will get you the boot from the dealership. Again it is because it is privately owned business. I think I could explain why they are passing the buck not helping you and using Mazda crop as the villain. But you would need to at least PM with some information for me to check out.