Author Topic: Remote key fob failing  (Read 459 times)

Offline Mike246

  • Newbie
  • *
  • Posts: 5
  • I NEED TO UPDATE MY SIGNATURE!!!
  • Body: SUV
  • Colour: Deep Crystal Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2019
Remote key fob failing
« on: November 16, 2020, 07:49:24 pm »
My 2019 CX-5 has been super reliable however the remote key fob has failed.

It started with a dash warning that the fob battery was low so I replaced it. The message has re-appeared so I tested the battery as good but replaced it again. Subsequently the remote will not open the doors nor the trunk but will start the engine if placed close to the starter button.

Needless to say, I am now using the spare remote, this works fine without a dashbaord warning.

I called the dealership for guidance and they said to book the car in and the work would be chargeable! I think not and if so, will roll the bill up tightly pending further action.

Anyone experienced similar or can offer advice?

Offline aljshep

  • Newbie
  • *
  • Posts: 30
  • .
  • Body: SUV
  • Colour: Soul Red Metallic
  • Engine: 2.2L 175ps
  • Fuel: Diesel
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2017
Re: Remote key fob failing
« Reply #1 on: November 16, 2020, 09:27:47 pm »
I would guess that the battery is not making proper contact with the key fob.
Is it properly located in position (and the correct way up)?
Is the fob damaged in any way so as to break electrical contact?
Failing that, I would assume that the electrical gizmos in the fob have failed.
Good luck!

Offline Mike246

  • Newbie
  • *
  • Posts: 5
  • I NEED TO UPDATE MY SIGNATURE!!!
  • Body: SUV
  • Colour: Deep Crystal Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2019
Re: Remote key fob failing
« Reply #2 on: November 16, 2020, 10:11:21 pm »
Aljshep, thanks for your response.

Certainly the new battery has been checked at 3.3 volts and is making good contact. The red LED blinks on pressing a button.

I share your belief is that the circuit board is faulty and the fob needs replacing.

Offline steve101

  • Jr. Member
  • **
  • Posts: 76
  • I NEED TO UPDATE MY SIGNATURE!!!
  • Body: SUV
  • Colour: Arctic White
  • Engine: 2.2L 150ps
  • Fuel: Diesel
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2018
Re: Remote key fob failing
« Reply #3 on: November 17, 2020, 09:18:48 am »
Have you used a good quality battery like Duracell? If not, fit one before the dealer sees it. They seem to be the type of dealer that is more concerned with money and might use the quality of battery as an excuse. I assume you are aware that there are different types of CR20 batteries, the last two digits referring to the thickness of the battery. I tried a CR2032 and it was too tight.

Offline Mike246

  • Newbie
  • *
  • Posts: 5
  • I NEED TO UPDATE MY SIGNATURE!!!
  • Body: SUV
  • Colour: Deep Crystal Blue
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Automatic
  • Year: 2019
Re: Remote key fob failing
« Reply #4 on: November 17, 2020, 11:25:10 am »
I've tried CR2025's of different makes. Both new and voltage tested. One flashes the LED the other doesn't.

It would appear that edge contact with the positive terminal of the cell is dependent upon minute manufacturing differences.

Fortunately the rest of the vehicle does not use the same precipice design.

Offline Gel

  • Full Member
  • ***
  • Posts: 136
  • New to Mazda; enjoying my new CX-5
  • Body: SUV
  • Colour: Soul Red Metallic
  • Engine: 2.0L 165ps
  • Fuel: Petrol
  • Model Grade: Sport Nav
  • Transmission: Manual
  • Year: 2019
Re: Remote key fob failing
« Reply #5 on: November 18, 2020, 08:04:41 pm »
Keyfob is very intolerant of battery voltage drop; worst I've ever known!
Even though I use fresh Maxell (Made in Japan) cells, sometimes it still shows fob warning
even with new cell inserted.
Gerald
Thames Valley
Ex Qashqai Tekna Diesel owner
(with zero road tax: I'll miss that :( )

Mazda CX-5 Forums

Re: Remote key fob failing
« Reply #5 on: November 18, 2020, 08:04:41 pm »