Seek Maintenance Advice for 2016 BMW i3 Rex (60k miles, Low Use)

BMW i3 Forum

Help Support BMW i3 Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

bmwni3

Member
Joined
Apr 18, 2024
Messages
8
Hi all,

I have a 2016 BMW i3 Rex with 60k miles, driving less than 1500 miles/year.
I changed the oil last year. Do I need to change brake fluid, cooling fluid, and air filter regularly, or are these just recommended?
Car parked in the sun for months, alarm beeps intermittently but stops in the garage, is it a battery issue or cooling fluid need to change?
Any insights or other maintenance tips for low-use cars?

Thanks!
 
Alarm going off while car is parked and no one around is either the 12v battery failing or you have something plugged into the OBDII port (like a tracker for insurance).

There is also an interior motion sensor alarm that could be triggered if you leave a pet in the car. If this is triggering a "false positive" with no pet in the car, you can try disabling the motion sensor alarm by clicking twice on the lock button on the fob after you exit the car and close the door but I am betting it is the 12v battery failing.
 
I am betting it is the 12v battery failing.
^This thing.
Also don't forget to change the blinker fluid every 2 years.
;) JK, about that . . .
. . . but serious about checking that old battery before you're stuck somewhere.
And keep enjoying your car, of course.
 
BMW recommends changing the brake fluid every 2 years. I've changed the brake fluid myself twice. I could not distinguish between the colors of the old and new fluid which led to me deciding that I could change to a 3-year schedule using Bosch extended life fluid.

There is no recommended cooling fluid change interval. There are 2 cooling fluids on all i3's: the cabin coolant and the propulsion motor and motor electronics coolant. I believe that REx models have a third coolant that transfers heat from the REx engine to the propulsion motor and motor electronics coolant. The REx coolant probably experiences higher temperatures than the other coolants so might need changing more often.

The cabin air filters need to be changed when they become dirty. How long that takes depends on how much the climate control system is used and how dirty the ambient air is. The cabin filters in our 2014 i3 looked clean after 4 years, but we don't use climate control as much as most i3 owners probably do due to our mild climate and very clean air.

The alloy wheels or the Bridgestone tires slowly leak air. I inflate the tires on our i3's every 3 months because they tend to lose ~5 psi during that period.
 
Alarm going off while car is parked and no one around is either the 12v battery failing or you have something plugged into the OBDII port (like a tracker for insurance).

There is also an interior motion sensor alarm that could be triggered if you leave a pet in the car. If this is triggering a "false positive" with no pet in the car, you can try disabling the motion sensor alarm by clicking twice on the lock button on the fob after you exit the car and close the door but I am betting it is the 12v battery failing.
Thank you so much for the tips. Is there more affordable place than dealer to get the 12 V battery replace? They charge $250 to diagnostic on the 12 v battery and $650/ each 12 V batter.
 
BMW recommends changing the brake fluid every 2 years. I've changed the brake fluid myself twice. I could not distinguish between the colors of the old and new fluid which led to me deciding that I could change to a 3-year schedule using Bosch extended life fluid.

There is no recommended cooling fluid change interval. There are 2 cooling fluids on all i3's: the cabin coolant and the propulsion motor and motor electronics coolant. I believe that REx models have a third coolant that transfers heat from the REx engine to the propulsion motor and motor electronics coolant. The REx coolant probably experiences higher temperatures than the other coolants so might need changing more often.

The cabin air filters need to be changed when they become dirty. How long that takes depends on how much the climate control system is used and how dirty the ambient air is. The cabin filters in our 2014 i3 looked clean after 4 years, but we don't use climate control as much as most i3 owners probably do due to our mild climate and very clean air.

The alloy wheels or the Bridgestone tires slowly leak air. I inflate the tires on our i3's every 3 months because they tend to lose ~5 psi during that period.
Thank you for all your reply. BMW dealer was saying I need brake fluid change and battery cooling fluid change, I am confused. They also said about range extender maintenance required due to prolonged period of parking( no use) , this maintenance is the oils change?
 
^This thing.
Also don't forget to change the blinker fluid every 2 years.
;) JK, about that . . .
. . . but serious about checking that old battery before you're stuck somewhere.
And keep enjoying your car, of course.
Thank you! Do you mean the mostly important issue influencing ability to drive is the 12 v battery ? The brake fluid might still be good, dealer just recommend to change on fix schedule
 
Thank you! Do you mean the mostly important issue influencing ability to drive is the 12 v battery ? The brake fluid might still be good, dealer just recommend to change on fix schedule
If the 12V battery starts to fail, you can get all kinds of seemingly unrelated errors ("Drive Train Malfunction!" "ABS Malfunction!" "Self Destruct Sequence Initiated!" etc.) on the screen and a car that possibly can't be started. There aren't any specific warnings about the battery about to croak, although you might infer the problem from other symptoms. The 12V battery doesn't last forever or even the service life of the car. If your battery is 3+ years old, I'd just replace it. I didn't listen to me, and ended up walking my child to school in January in the Midwest.

That $650 bid you got for the battery sounds high, more than I remember paying 2 years ago.
 
If the 12V battery starts to fail, you can get all kinds of seemingly unrelated errors ("Drive Train Malfunction!" "ABS Malfunction!" "Self Destruct Sequence Initiated!" etc.) on the screen and a car that possibly can't be started. There aren't any specific warnings about the battery about to croak, although you might infer the problem from other symptoms. The 12V battery doesn't last forever or even the service life of the car. If your battery is 3+ years old, I'd just replace it. I didn't listen to me, and ended up walking my child to school in January in the Midwest.

That $650 bid you got for the battery sounds high, more than I remember paying 2 years ago.
Thank you soooo much for your quick reply. Your post just reminded me of the FALSE ALERT I receive when purchase the car. I wasn’t aware that was could be the 12 V battery issue since this is my first car. FALSE ALERT like “drive train malfunction” , “low tire pressure but in fact the tire pressure was all great, checked at the dealer” The car motion alarm go off intermittently when no one near.
Since $650 / per 12 V battery is too high + $280 diagnostic fee to check which battery is failing . I am checking other mechanics places.
Do you get same quality 12 V battery replacement in Non- BMW dealer like JIFFY Lube ?
 
I've only replaced one battery in my i3 and that was at the dealer since I'd waited too long to shop around, but other members have had a lot more experience and will be able to give more relevant advice soon.
 
The OEM battery in all U.S. i3's is an East Penn Manufacturing AUX18L. It can be ordered from Remy for a lot less money than BMW dealers charge. It is not difficult to replace. There are excellent YouTube videos that show how to replace the battery in detail. If you'd rather not do it, maybe there's an independent BMW mechanic who would do it for far less than a BMW dealer would charge.
 
Hi all,

I have a 2016 BMW i3 Rex with 60k miles, driving less than 1500 miles/year.
I changed the oil last year. Do I need to change brake fluid, cooling fluid, and air filter regularly, or are these just recommended?
Car parked in the sun for months, alarm beeps intermittently but stops in the garage, is it a battery issue or cooling fluid need to change?
Any insights or other maintenance tips for low-use cars?

Thanks!
If you have vehicles without the 2-yr brake fluid service reminder you can test your fluid with a tester from amazon for under $20 "Brake Fluid Liquid Tester Pen" and change the fluid before it reaches 3%. The brake fluid reservoir on your i3 is under the velcro panel on the right side of your frunk box with the yellow verbiage "clean filler cap before opening".

If you work on your own cars check out the "motiv brake fluid dry method" it is something I started doing a decade ago due to the pressurized line bursting on a motiv bleeder and spraying me with brake fluid.

Wet boiling point is the temperature where brake fluid, which has absorbed 3.7% of water by volume, begins to form gas bubbles.
Moisture in brake fluid also causes metal brake parts to rust and corrode from the inside out (aka a rotted-through brake line), and rubber parts to swell, deteriorate and weaken.
 
Back
Top