starting the range extender for emissions testing

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FrancisJeffries

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May 15, 2014
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This is copied (but I couldn't get rid of the underscores :( ) from Section 10 of the 12-W20 Engine.pdf:

10.1._Exhaust-gas_test_mode
It_is_necessary_to_start_the_combustion_engine_for_an_exhaust-gas_test_in_the_BMW_I01_with_range extender._This_is_made_possible_by_a_certain_operating_sequence:
• Tailgate_is_open
• Switch_on_ignition_and_engage_drive_position_"P"_(without_braking)
• Press_and_hold_down_the_accelerator_pedal_within_60_seconds
• Press_the_brake_three_times_within_20_seconds_and_hold
• Release_the_accelerator_pedal_and_press_the_START-STOP_button_when_the_brake_is_actuated
• The_combustion_engine_starts_if_the_SOC_of_the_high-voltage_battery_is_less_than_75 %.
As_a_Check_Control_message_the_status_"Exhaust-gas_test_mode_activated"_is_output_when_the combustion_engine_is_running._The_empty_run_point_is_automatically_approached_during_the_warm-up phase._Using_the_pedal_sensor_position_two_speed_points_of_the_combustion_engine_are_selected_for the_measurement.
The_"Exhaust-gas_test"_mode_is_automatically_ended:
• after_20 minutes
• or_at_the_start_of_the_journey
• or_by_switching_off_the_ignition.
 
Do you know if it charges the battery during that cycle?

If yes that could be used as nice quick charger option, 20 minutes would probably charge good 5kWh into battery (assuming it's depleted deep enough to accept that charge).
 
KMP647 said:
easy to do, glad I did it as the fuel was a bit old. energy screen does show it charging the battery for about 5 minutes then it stopped adding charge
does not seem like a practical method to charge the battery.
thank you
Probably not for everyday use, but could be used in a pinch to get you over that 10000ft pass without reduction in power?
 
The test mode will charge the battery - that is why you have to be under 75% to begin the test and it only runs a certain period time to avoid over-charging. i.e.
 
I speak from experience here, do not bank on the test mode gaining you very much in terms of battery percentage. In 15 minutes at low speed it regained about 6%, have not sat with my foot on the throttle to know if the high speed does much better. From my understanding, during this inspection test the engine is not heavily loaded(partial generator load only). Emissions testing is not usually done at full load, just at idle and high idle.
 
BMW desperately needs to update the software for the I3 so when you start he engine at a reasonable SOC say anything below 50% - if the car is not demanding the current - the RX can charge the battery - what's the sense of having the engine running to merely hold the state of charge, why not bring a 50% battery back to 75% if you're not demanding the current - a typical situation would be driving around in city traffic.

On my I8, if I shift to Sport mode the onboard generator attached to the engine will charge the battery up "one mile for each two miles I drive" - in 20-30 minutes of driving, I can add back 12 miles to my battery. The RX generator is more than capable of achieving this!

Mike
 
The i8 has over 200hp, and thus has plenty of output under normal driving to be able to recharge the batteries up to their full capacity while driving the car down the road quite briskly. The i3's 34hp REx is unable to maintain charge, let alone recharge, the batteries if you are stressing things. Yes, around town, it will have excess capacity, and, to a small amount, does recharge the batteries, but it is not designed to top them off...different cars, different priorities and operating characteristics.
 
Why would you want to charge your battery with that (relatively) inefficient generator?
 
jadnashuanh said:
The i8 has over 200hp, and thus has plenty of output under normal driving to be able to recharge the batteries up to their full capacity while driving the car down the road quite briskly. The i3's 34hp REx is unable to maintain charge, let alone recharge, the batteries if you are stressing things. Yes, around town, it will have excess capacity, and, to a small amount, does recharge the batteries, but it is not designed to top them off...different cars, different priorities and operating characteristics.

Absolutely Not True the I3 RX engine and generator combination is a powerful high output generator.

Since the I3 Range extender is large enough to supply power to run the car at 75 mph with accessories, it could easily charge the battery back up to 75% in just minutes - the I3 RX combination produces an amazing 24Kw.

Since the I3 was designed as a "Plug In Car" the RX is designed to do just that - extend range but not charge the batteries. BMW did not elect to provide software for a charge option.

In fact -the generator on the I3 is larger than that of the I8!
 
What seems to be missing here is that in the i8, it can easily drive itself on the ICE all day AND recharge the batteries. The i3's REx is large enough to keep it running at speed IF you aren't also trying to climb a long hill and have all of your comfort features enabled. Lots of people report their REx can't recharge the car while climbing a grade. Yes, at lower speeds, there is excess generating power, but to extend maximum range, they run the thing slower to maintain, rather than recharge, or maybe gradually bump it up to 75% as implemented in the rest of the world.
 
This is why I installed the DVDinMotion Patch that allows me to manage my battery instead the processor - I think its great that the I3 starts the RX when the battery gets down to 6% for the driver who was unaware. But as we all know, getting the I3 to 6% SOC results in problems.

For myself, I prefer to have to leave 25% or so in the pack in the unlikely event I experience a non starting engine or even running the RX out of fuel, I can travel off the highway to a place that is safe.

Here's my review on the Engine management :

http://www.mybmwi3.com/forum/viewtopic.php?f=2&t=2141

Mike
 
When the REX kicks in that should be your sign that you need to get to a charging station. The REX motor was not installed so you can continue to drive your car for another 60 miles. I'm reading all over this forum is how people are trying to get the REX turned on sooner, or using it to continue driving. It is simply there to help get you to a charging stations when you get to about 6.5% SOC. If you want to have an electric car that runs on gas then go buy a volt. For greater range, my suggestion is to take advantage of the eco pro options. These cars are very smart and can help you get the most out of every charge.
 
Idleup said:
This is why I installed the DVDinMotion Patch that allows me to manage my battery instead the processor - I think its great that the I3 starts the RX when the battery gets down to 6% for the driver who was unaware. But as we all know, getting the I3 to 6% SOC results in problems.

For myself, I prefer to have to leave 25% or so in the pack in the unlikely event I experience a non starting engine or even running the RX out of fuel, I can travel off the highway to a place that is safe.

Here's my review on the Engine management :

http://www.mybmwi3.com/forum/viewtopic.php?f=2&t=2141

Mike
Does anyone have any opinion on which coding service is preferable - DVDinMotion or CodeMyCar ? I see on CodeMyCar's site that they now have coding for the REx full tank capacity.
 
I01Specialist said:
When the REX kicks in that should be your sign that you need to get to a charging station. The REX motor was not installed so you can continue to drive your car for another 60 miles. I'm reading all over this forum is how people are trying to get the REX turned on sooner, or using it to continue driving. It is simply there to help get you to a charging stations when you get to about 6.5% SOC. If you want to have an electric car that runs on gas then go buy a volt. For greater range, my suggestion is to take advantage of the eco pro options. These cars are very smart and can help you get the most out of every charge.


Absolutely wrong!

The RX motorcycle engine is not a patch or intended to "Only" to get to the next charging station. The engine can be used as you would any electric / gas car similar to the Volt. The only difference is the engine is much smaller on the I3 and therefore works a bit harder. IN fact you could use it every day if you like for local travel, many owners do.

I have this same engine in my BMW 650 Sport with 64,000 miles they are bullet-proof in construction and made to last for decades. The only thing i would recommend is if you're using the RX to travel Like I have on numerous trips from Ga to Fl, that you keep you speed around 60 mph to avoid drawing the battery down any further.

Regards Mike
 
The RX motorcycle engine is not a patch or intended to "Only" to get to the next charging station.

Exactly!

The limited access to the REx motor is unique to America - it was operationally 'crippled' to qualify the i3 for specific EV State/Federal benefits for BMW, nothing more.

BMW actually designed the REx to be used as it is in the rest of the world where the engine can be run on-demand to extend range.
 
Unlike in the US, there are a lot of places in Europe where you will pay a different toll, if allowed at all, if your vehicle is using the ICE. So, as a result, preserving the battery capacity so you can be running only on batteries can save you a bunch of money and sometimes, even access to certain areas. So running the REx on demand can mean you will have enough battery capacity to enter and run around the city center and save money and gain access.

BMW did not want to include the REx, but marketing forced the issue. When used as intended, as a city, commuting vehicle, running on batteries was the preferred mode of operation. THe added weight and complexity of the REx was a detriment deemed useful to help make the switch to an EV more palatable.

It's a tribute to the design that you can use the REx to take the car on extended trips. If they really wanted you to do that, they'd have put a larger fuel tank on the thing. The size of the tank means you'll be stopping nearly every hour or so, which isn't the quickest way to get anywhere.
 
All I'd like to see is turn on the rex at low rpm. I don't care if it's not maintaining charge. Running the rex at 2k rpm, reduces the battery load, and may actually get you to the hwy exit 50-100 miles away, without hitting the 6% mark. Once you're at the exit, the vehicle can easily gain soc as you cruise around, without needing to see a charging station. It would also help in case the charging stations are slow chargers. Both rex + L1 or L2 charger combined could give you near to L3 charging, when in a pinch.
 
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