2018 Mazda CX-5 Various Electrical Issues

[RedBaron]

I seem to recall seeing on here that there was a known problem with the liftgate mechanism draining the battery. I'll see if I can find it.

UPDATE: This was what I found, but may not apply to your car: https://static.nhtsa.gov/odi/tsbs/2020/MC-10180692-0001.pdf

 

[SparkYellow]

For my 2017 CX-3, the original battery started to act out in 6/2023. Over the span of a couple of months, every time I finished loading/unloading from the hatch, the car would need to get jump-started. The hatch mechanism seems to draws quite a bit of wattage when left unlocked for more than half an hour, but a good battery would have enough juice to accommodate it.

My replacement battery from AutoZone failed in two years.

 

[calmad55]

Ah, great, thanks for this. This makes sense then aligned to that recall, I suspect its a combination of malfunction of the PLG control module not going to sleep/power saving mode despite ignition off and it's sucked the life out of the battery (quickly, given the large draw from the battery).

After reading that recall and further googling, seems a parasitic draw from the battery linked to the PLG module isn't uncommon

 

[calmad55]

Progress update - new PLG control module installed, battery recharged and car drives / stop / starts perfectly, so would have thought reasonable battery life to have this working.

if anyone happened to have any further ideas id be greatly appreciated before getting mazda to look at greater expense. It's like the mechanism is confused in sequence or the release is getting caught - unsure if a battery in poor health/ 'on the way out' would also cause this? I presume the struts are fine as it has worked intermittently as noted beforehand

 

[CrazyHippie]

TLDR: Lift gate, infotainment screen, head up display, key less entry, keys, heated seats, heated steering wheel, interior lights, USB’s, and trip monitor stopped working suddenly. Car runs fine. Battery checked multiple times and showed to be “good”, and no fuses appear to be blown.

I have a 2018 Mazda CX-5 Grand Touring AWD. About two weeks ago the lift gate started to intermediately not want to open and give 3 beeps. It would not open with the key, rear button, or driver side button. Disconnecting and reconnecting the battery would temporarily fix the issue or over time it would decide to work on its own, but it kept returning.

A week after this started, I got a check engine light and took the car to O'Reilly to get the codes checked and to get the battery checked. The codes were U0100, U0115, U0121, and the battery and alternator showed good on the tests with the battery installed in the car. The check engine light would go away and come back randomly it seemed.

Several days later it all got worse. The lift gate issues persist but now the infotainment screen (tried back+nav+mute but nothing happened), head up display, key less entry, keys (not responding to both keys and have to place them next to start button to start the car), heated seats, heated steering wheel, interior lights, and USB’s in the console don’t work. Also the trip monitor resets after each drive. I took the battery out of the car and got it tested again at O’Reilly and the battery tested good again, it is an Optimum RedTop that is 2.75 years old. I tried checking all the fuses in the engine compartment and under the steering wheel and didn’t see any that looked bad.

The car seems to run fine otherwise. I just have to unlock/lock the car with the physical key.

Does anyone have any idea what could be causing all of these issues?

One thing that may be a cause is mouse/ chipmunk/ squirrrel damage from chewing wires up under the car and/ or under the hood.

One of the measures that car manufacturers have taken in order to claim carbon credits under environmental regulations is to move away from petroleum-based materials to 'green' materials One such change that not many people are aware of is wiring insulation. They have changed from plastic to a soy-based alternative. Guess what?Yep, the soy based wire insulation has a taste/ odor that attracts rodents! So they crawl up into your car, make nests and chew on the tasty wiring. Honda actually sells a capsaicin-impregnated wire wrap for $50 a roll (or so) to repel the buggers!