i-Stop BATTERY CONDITION INITIALIZATION SETTING
Caution:
• If the engine is started with the hood open, i-stop will not operate until the hood is closed and the engine is re-started (Not a system malfunction).
If the engine was started with the hood open, switch the ignition OFF, close the hood, and then restart the engine.
Without Mazda M Hybrid
• If the vehicle is brought in with i-stop not operating, the malfunction cannot be resolved by only performing this battery condition initial setting (i-stop setting).
Have the Battery value determined by the PCM.
1. Disconnect the negative battery terminal and wait for 5 min or more.
Note
• It is necessary to leave the battery undisturbed for 5 min or more because the voltage may not be stabilized depending on the battery usage condition and it could cause the PCM to determine the BATTERY value incorrectly.
2. Disconnect the current sensor connector.
Have the PCM learn the battery condition.
1. Connect the negative battery terminal and wait for 10 s or more.
2. Connect the current sensor connector.
Note
• If the current sensor connector is connected first before connecting the negative battery terminal, the PCM may mistakenly recognize a signal from the current sensor and learn the battery condition incorrectly.
3. Switch the ignition ON (engine off) and wait between 15 s to 60 s.
4. Press and hold the i-stop OFF switch for approx. 10 s.
5. Verify that the i-stop warning light (amber) illumination changes to the i-stop indicator light (green) flashing.
• If the i-stop warning light (amber) does not turn off, it is possible that the procedure was performed incorrectly, therefore, perform the procedure again from the beginning.
• If the i-stop warning light (amber) flashes, perform a battery inspection.
6. Switch the ignition OFF.
7. Close the hood
Perform idle air control learning.
1. Switch the ignition ON (engine on).
2. Turn off the following systems to which electrical load is applied.
• Lighting systems such as headlights.
• Climate control system
• Rear window defogger
3. Warm up the engine completely.
4. Switch the ignition OFF.
Verify the i-stop control settings.
Perform the following procedure from Step 1. to Step 5. within 25 sec.
1. Switch the ignition ON (engine off) and within 5 sec, press and hold the i-stop OFF switch for 3sec or more.
2. Verify that the i-stop warning light (amber) is on.
3. Switch the ignition ON (engine on).
4. Verify that the i-stop warning light (amber) illumination changes to the i-stop indicator light (green) flashing.
• If the i-stop warning light (amber) illuminates or flashes, perform a battery inspection.
5. Press and hold the i-stop OFF switch for approx. 3 sec.
6. Wait for 30 sec while idling (with no electrical load).
7. Perform engine racing for a minimum 10 times and a maximum 20 times. Then, wait for 30 sec while idling (with no electrical load).
• After the flashing i-stop indicator light (green) turns off, switch the ignition OFF.
• If the i-stop indicator light (green) does not turn off, it is possible that there is a problem with the Mazda M Hybrid system, therefore, perform an inspection of the Mazda M Hybrid system.
Note
• Depending on the battery condition, the i-stop indicator light (green) may stop flashing and turn off early, and the i-stop control setting verification may be completed early.
8. Maintain the idling condition (with no electrical load) until the i-stop indicator light (green) turns off.
9. After the flashing i-stop indicator light (green) turns off, switch the ignition OFF.
Perform an i-stop control operation verification.
1. Switch the ignition ON (engine on).
2. Accelerate to a vehicle speed of 15 km/h in approx. 5 sec without operating the steering wheel.
3. Stop the vehicle.
4. Verify that the engine stops and restarts by the i-stop control.
5. Switch the ignition OFF.

From my years I find the usual reason newish car Batteries Fail (or go flat) is because the owner fails to perform very simple and basic Battery Maintenance, that is to make sure your CX-90's Wet Lead Acid Cells (under the plastic screw bolt you un-screw to remove) has enough fluid in EACH CELL, if they are left dry or you can see the side edges of the lead plates then it is usually too late (not always).
However, BEFORE it gets to this ALWAYS make certain you have a bottle (litre or quart) of distilled water on-hand and a clean small plastic syringe so you can easily fill each plate so there is at least a minimum of 5mm or 1/4 inch of fluid over Each Plate.
During summer check every 3 months, winter at the start and end of. As you drive your car the battery will hold an excellent charge and convert fresh distilled water in car battery to the required electrolyte (sulfuric acid).

Please Note: If you continue to have issues with your cars i-Stop - Battery - Dash Warning Lights please see your Mazda Dealer as your car ''may need'' a higher level of attention with MDARS Diagnostics.

 

Reserved

 

Hi ASH8. Can you give me some tips to disconnect the negative? It seems to be hidden back so I am not sure how to proceed. I am planning to add some illuminated trunk scuff and Welcome lights that is why I need to unplug the negative terminal.

 

Sorry for late reply..

Disconnect always POSSITIVE First, (any minor short goes to Ground or Negative or Body)

Reconnect always NEGATIVE or Ground Cable First.

 

Just to confirm, if we are talking about the car's 12v battery and I presume this to be universal, generally the negative terminal should be disconnected first and reconnected last (opposite). The positive terminal won't exactly run hot by first removing the negative (grounded) terminal. By removing the negative first, you are essentially killing the positive terminal's power (not entirely, but effectively). This is to avoid risk of spark/fire/electrocution. Same concept for using jumper cables.

 

Hi ASH8. We just bought are 2024 Mazda CX-90 three weeks ago. Our son left the trunk open without us knowing now a couple hours later it's completely dead. My husband tried to jump and it's still dead. Any idea what could be the problem?

 

When you say jump start, I hope you don't mean push start as it is Automatic, which you can't do.

So you put Jumper Leads on Battery, yes.. if so AFAIK Mazda CX-** (double digit) of any model won't permit any quick starting with a power pack or jumper lead as Control Units monitors charge hold status and CCA status, from memory connected Cars Battery must hold a minimum of 65% charge.

As your cars Battery was drained flat leaving Trunk Light on, (done it myself with interior light), YOU need to purchase a Battery Charger like the CTEK MXS 3.8 is a good all-round investment and less than $100.
Disconnect Positive Lead and connect the alligator clamps on the two battery posts.
Red Possitive +, Black Negative or Ground - .
Leave it powered on cars Battery for a full day and overnight, by the following morning car should start.

Really is no other way with a dead flat battery in 2025.

 

When you say jump start, I hope you don't mean push start as it is Automatic, which you can't do.

So you put Jumper Leads on Battery, yes.. if so AFAIK Mazda CX-** (double digit) of any model won't permit any quick starting with a power pack or jumper lead as Control Units monitors charge hold status and CCA status, from memory connected Cars Battery must hold a minimum of 65% charge.

As your cars Battery was drained flat leaving Trunk Light on, (done it myself with interior light), YOU need to purchase a Battery Charger like the CTEK MXS 3.8 is a good all-round investment and less than $100.
Disconnect Positive Lead and connect the alligator clamps on the two battery posts.
Red Possitive +, Black Negative or Ground - .
Leave it powered on cars Battery for a full day and overnight, by the following morning car should start.

Really is no other way with a dead flat battery in 2025.

When you say jump start, I hope you don't mean push start as it is Automatic, which you can't do.

So you put Jumper Leads on Battery, yes.. if so AFAIK Mazda CX-** (double digit) of any model won't permit any quick starting with a power pack or jumper lead as Control Units monitors charge hold status and CCA status, from memory connected Cars Battery must hold a minimum of 65% charge.

As your cars Battery was drained flat leaving Trunk Light on, (done it myself with interior light), YOU need to purchase a Battery Charger like the CTEK MXS 3.8 is a good all-round investment and less than $100.
Disconnect Positive Lead and connect the alligator clamps on the two battery posts.
Red Possitive +, Black Negative or Ground - .
Leave it powered on cars Battery for a full day and overnight, by the following morning car should start.

Really is no other way with a dead flat battery in 2025.

I have used a L-ion battery pack for years, but understand the logic on the electric system and will only use a charger. Thanks for the tip, wouldn't fry anything!