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Keyless System Malfunction and unable to start

I'm having an issue with my 2018 CX-5 and was hoping to get some help.

I'm unable to start the car. This is after the car was left sitting for 4 days. Initially I though it was an issue with the battery, but still unable to start even with a jump. I'm getting an error message of "keyless system malfuction" and the ignition light blinks red. I've tried replacing the keyfob battery, trying a second keyfob, holding the keyfob right up to the ignition switch, all without success.
The keyfob is recognized via pressing the button on the driver side door to lock/unlock

Any suggestions of things to try next, before I get it towed to a mechanic or dealer?
 
:
2014 & 2019 CX-5 Touring(s)
First did you fully recharge the battery? Then, have you tried to disconnect the negative battery terminal for a few minutes and reconnect and retest? The ECM/BCM may just need a deep restart (hope).
 
:
2014 & 2019 CX-5 Touring(s)
Yayy!

Not sure how old your car and battery are - if they are old you'll probably need a new battery. If not old, then go get a battery charger and hook it up for several hours. Running that low is not good for car batteries.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg. Plano, TX
Contributor
:
Plano, Texas, USA
Yayy!

Not sure how old your car and battery are - if they are old you'll probably need a new battery. If not old, then go get a battery charger and hook it up for several hours. Running that low is not good for car batteries.
OP said it’s a 2018 and I assume the battery should be fine. He should bring his 2018 CX-5 to his Mazda dealer checking up the problem. Hopefully there’s some error codes saved at this time. Dealer should be able to check the battery too if the battery capacity is not within specs. The factory battery may still have some warranty left if the culprit was really the weak battery. The car should be able to start without any problem after just 4 days of sitting.
 
:
2018 CX-5 Sport
Take it to the dealer and say you got a 'keyless system malfuction' and have them check it out. The last thing you want is to be stranded somewhere if it happens again. It is a PITA to go, especially if it is working fine now, but you should get it checked out.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
OP said it’s a 2018 and I assume the battery should be fine. He should bring his 2018 CX-5 to his Mazda dealer checking up the problem. Hopefully there’s some error codes saved at this time. Dealer should be able to check the battery too if the battery capacity is not within specs. The factory battery may still have some warranty left if the culprit was really the weak battery. The car should be able to start without any problem after just 4 days of sitting.
I was thinking the same thing.

For goodness sake, people take vacations and leave older cars/batteries than this sitting for a week or longer, and [rightfully] expect the battery to turn the thing over. This is not "long term storage."
 

erhayes

Contributor
:
Mazda CX-5 FWD Touring
Brake pedal switch or transmission switch could be the problem. Try moving the shift lever around and hit the brake pedal several times to see it that gets you going. Ed
 
For goodness sake, people take vacations and leave older cars/batteries than this sitting for a week or longer, and [rightfully] expect the battery to turn the thing over. This is not "long term storage."
I wonder if there is a parasitic drain when the key is left inside the vehicle while powered off. I've read of others with power issues after the keys were left in the car for multiple days. Maybe it triggers the dome light to stay on, or some other trigger?
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
I wonder if there is a parasitic drain when the key is left inside the vehicle while powered off. I've read of others with power issues after the keys were left in the car for multipledays. Maybe it triggers the dome light to stay on, or some other trigger?
My 2019 manual says:
If a key is left in the vehicle, the functions of the key left in the vehicle are temporarily suspended to prevent theft of the vehicle. To restore the functions, press the unlock button on the functions-suspended key in the vehicle.
I'm not certain what model years this applies to.
 
:
2018 Mazda CX-5 GT
My keyfob battery was running low last year and the system indicated that my battery should be replaced. I can't remember the specific message...replacing the battery worked.

I left my car sitting out for 20 days while I was traveling and it started up just fine. OTOH, there was so much rust accumulated on the brake rotors that I drove it 2 miles hearing a thump thump thump until braking/driving the car cleaned off the rotors.
 

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