2014 CX-9 charging system problem

Hello, I have 2014 cx-9 grand touring which has a charging system problem. Replaced battery and alternator (alt 2times) battery light started coming on and off intermittently and charging rate steadily decreased from 13.8 to not charging at all now. I kept oem alternator and replaced regulator and rectifier in it and reinstalled it, still no charge. All voltages are correct on plug and stud. Probed wires back to pcm all ok. I’m thinking either pcm failed ( car runs great) or another sensor is interrupting charging circuit, I’ve read Mazda has iat sensor in that circuit but don’t show it on diagram. Any help greatly appreciated wife needs her car back!
 
No CEL and codes (including pending ones)? OBD live data stream might provide some helpful charging system information from the ECU.
 
That’s my next step, went to buy scan tool yesterday but didn’t like what was in stock. No codes with basic code reader.
 
The most popular option for live data scanning these days is to buy an adapter (dongle) for $20 or so, and a phone app. There are a number of free OBD apps, however a low cost one such as Torque Pro will provide additional PIDs, beyond what the free ones give. And for the problem your vehicle is having, I'd want every bit of data that's available.
 
I’d like a tool with bidirectional testing and relearn so probably upwards of 400-500$ I’m assuming. I’ve had snap on and such in the past years but left industry 17 years ago so kind of out of the loop.
 
If that's your plan, I strongly recommend doing all of the research necessary to assure you're getting everything you're looking for. Nine years ago I bought a Creader OBD reader, which in the past has been a very solid unit. Not in the class of the unit you're looking for, but it did have extra functionality, such as TCM and ABS.

However, when attempting to use it with the CX-5, I've discovered that the support for the unit is basically non-existent. They did provide an online software upgrade, which presumably includes the newer CX-5, however there's a bug which makes it unusable. I've tried every online support source I can find, but there's been no response from any of them. So for the CX-5 I've been using Torque Pro for Android, which isn't as comprehensive as Creader, but does provide all I need for now.

So I'm telling you this sob story as a warning about trying to get help with issues after you buy the unit. You might wind up being more fortunate than I've been getting help, but it would be much better if you were certain it can do everything you want it to, before you buy.

Have you been able to find a charging system schematic for your vehicle?
 
I’m with you, I’m reading lots of reviews about non existent after sale service. Yes I checked a schematic: b+, ign and 2 wires to pcm all test ok voltage wise and pin out ok to pcm, unfortunately due to circumstances I’d prefer not to go to dealer until last resort.
 
Have you tried running it with the multi-wire plug disconnected from the alt? In many of the smart charging systems, if the regulator isn't getting valid input from the ECM, it will switch to outputting a constant 14V+ voltage. Don't know if that's the case with your specific vehicle, but it might be worth a quick test, if you have not already done so.
 
I have and I also fabricated an adapter to check it on car without the plug and it charged somewhat but I don’t have a module to duplicate pcm action.
 
Where you wrote 'charged somewhat', are you referring to voltage you read on one of the pins of the multi-wire plug on the alt, or do you mean voltage that was being output at the B+ stud? And if it was at B+, what was that actual voltage reading?
 
Ok I borrowed a top line scanner and did retry a po625 code f circuit to regulator. My voltage checks were at b+ and ign and l terms all read with battery voltage live data shows f duty cycle staying steady at about 55% and expected voltage 14.24. Actual voltage is still only 12 and I know f should be moving around depending on load requirements. I’m starting to suspect alternator again but still not 100% on field duty cycle at 55% and still not charging I guess I’ve been out of the business too long now (17 years) for my brain to wrap around this parameter.
 
If your testing shows that voltage is getting to the F pin of the ECM side of the plug, then yes the only remaining point of failure is the alternator itself, provided there's not a problem with the connector, or it's not 'clicking' in solidly.
 
Update decided to remove alternator one more time. I disassembled the oem and aftermarket alternators and checked the stator based on the dtc pointing to fields. Oem stator ( although I checked it originally when I pulled it off, but probably not thoroughly enough) seems to be shorted within the wye to the other 3 leads ( it has 6 lead connections). The aftermarket stator is shorted on one set of leads to ground, either way evidently I have 2 bad stators.
 
Nice diagnostic work, and good to read you got it figured out! Happy wife, happy life(y)
 
Well until it’s charging I’m not gonna jinx it lol and you are right!
Shut the front door! I'm going through the same thing! I've replaced the alternator TWICE! Also the battery, I am loosing my mind why there is no current going to the battery to charge. I went to a neighborhood junkyard and picked up a BCM thinking it could be sending a signal for some reason to not send current to my battery, and nothing...I even saw a CX-9 with the entire front end gone. I considered taking off the used alternator, this is getting ridiculous. I have a 2008.

What ended up happening to this?
 
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