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Why is Actual Mileage << Charge Mileage Used ?

Why is Actual Mileage << Charge Mileage Used ?

Does anyone know why the actual mileage tracked on odometer (lets name it AM) is so low as compared to the amount of charge mileage (CM) used for any given trip ?

I have a 2 month old Model S p100d that I notice about a month after purchase the AM << CM used. As you know the odometer does not appear on the dash unless specifically selected. So once I realized something was amiss, I started writing down start and end odometer and charge readings .... turns out AM is always only 60% of CM used. For instance, say you went on a 60 mile trip (real miles) but you check your charge mileage used up for the trip and its 100 miles. It doesn't seem to matter how the car performs or preconditioning. Its currently 50 to 80 degrees where I live and car is always garaged. Ive tried going on granny trips with nice easy driving and same....always only 60% of charge mileage (CM) used

Thanks for any advice as Tesla is not responding.

UnshodBob | 23 mai 2017

What is your average wh/mile? Do you keep your tires properly inflated? Mine need 45 psi cold, not 32 like in my old car. Check the driver's door sticker for your tire pressure requirements. Do you drive 80+ mph on the freeway? Do you drive a lot of stop and go city miles? You say the temperatures are moderate, so extreme cold isn't a factor. There are many variables that affect your actual kwh used per trip.

Ed D | 23 mai 2017

Tire pressure is right on - checked that first even before I called tesla.

Its mostly highway mileage but as I said it doesn't seem to matter what driving conditions. I can take a short survey any time during a trip and the AM always about 60% CM. Its almost like they put the P60 battery in my car is the only explanation Ive come up with as an EV newbie.

Ed D | 23 mai 2017

Tire pressure is right on - checked that first even before I called tesla.

Its mostly highway mileage but as I said it doesn't seem to matter what driving conditions. I can take a short survey any time during a trip and the AM always about 60% CM. Its almost like they put the P60 battery in my car is the only explanation Ive come up with as an EV newbie.

UnshodBob | 23 mai 2017

Did you read the owner's manual companion? Check the charging and range section.

https://forums.tesla.com/forum/forums/owners-manual-companion-faq

(I removed the reference to page 13 in the link, so I hope it still works.)

Bighorn | 23 mai 2017

My actual mileage is better than my rated mileage recently. Do you show rated or ideal miles? Very few people achieve ideal mileage, but rated isn't too hard to match going less than 70 MPH.

Ed D | 23 mai 2017

Yes I read the Manual. The car under performs regardless of charge method. Heres an example; A few weeks after I discovered this problem, I had an upcoming trip of 135 miles and without any superchargers within 30mi of destination. I could only make it to the destination with about 25 miles of charge left after leaving home with 294mi charge. (how is car supposed to be able to go 315 miles yet with all highway driving it can only make 160miles) Anyhow, I hit a supercharger on the way in middle of trip to add 150 mi of charge. Pulled away from supercharger and immediately began taking a survey -> same 60% of distance achieved. Repeated the survey and super charger visit on way home with same exact results.

UnshodBob | 23 mai 2017

I have a 2015 P90DL and am showing under 300 wh/mile on average. I'd expect a newer P100D to do about the same. I think the range for your car is much more than 11% higher than mine. At 100% I show about 255 miles, and at 90% I show about 230 miles on the dash. I can drive over 200 miles even at 90% SOC. Projecting 11% bigger battery should give 283 @ 100% and 255 @ 90% for your car. How does that compare with what you are seeing?

Ed D | 23 mai 2017

Bighorn thanks for response and confirming my belief something is wrong. As I said Ive tried every thing from driving nice and easy and test charging at superchargers all with same poor results. I tried driving with Range mode "On" and Sport mode selected and not using climate control as its so mild here. Same results doesn't matter what I do and Tesla won't even look at car or admit something wrong.

UnshodBob | 23 mai 2017

@Ed D - reading the Tesla manual is great, but the Owner's Manual Companion topic that I linked to contains a lot of information from actual owners who have experience with the car. Check it out! :)

UnshodBob | 23 mai 2017

Controls/settings/trips will show you the wh/mile average for the current trip, since last charge, and each of the two trip meters. What do those say? You should see miles, wh/mile, and kwh used I think. One shows the elapsed time instead, but those numbers will tell us something about your situation. If your wh/mile is 400-450, then you're using a lot of electricity to move the car. Please look up those numbers and post them.

Ed D | 23 mai 2017

Bob - thanks for all the responses. My car at 100% says 315 mi charge. I have only charged it up to 294mi once though due to warning about max charging shortens its life span. Anyhow, furthest I could drive before being out of power is 160 mi.

Ed D | 23 mai 2017

Bob - ok I will check those data points. Not sure what good that does since long and short, no possible way to go further than 160mi. How is there not something wrong with this car thats advertised as 315mi range. It won't even come close to your P90DL range over 200miles at 90% charge used.

UnshodBob | 23 mai 2017

That 200 miles is all freeway from home in SoCal to Quartzsite AZ. The car does better in heat, oddly. I have driven that route several times and have not had any trouble getting 200 miles from even a 90% charge. 160 is too low.

315 is about 30 miles more than my calculation predicted. That's another 10% higher! My numbers are just a little higher than the 85 batteries were showing. Anyway, you really just need enough to get to the next supercharger. 200+ is good for me. Your car seems like something is not right, but I still haven't seen your wh/mile numbers.

UnshodBob | 23 mai 2017

Here are my numbers for the first 12,500 miles.

Trip A 12,528.7 miles, 3,855.4 kWh, 308 wh/mile.
Trip B 2,197.3 miles, 664.8 kWh, 303 wh/mile.
Since last charge 68.7 miles, 17.7 kWh, 258 wh/mile.

This is mostly SoCal driving, moderate temperature, mix of freeway and city maybe 60/40 due to some long trips.

UnshodBob | 23 mai 2017

Here are my current numbers.

Trip A 8,980.8 miles, 2,609.6 kWh, 291 wh/mile.
Trip B 1,118.7 miles, 336.7 kWh, 302 wh/mile.
No data for since last charge because it charged up last night and I haven't driven it today.

UnshodBob | 23 mai 2017

P.S. I only reset Trip A when I go in for 12,500/25,000/etc service. So lifetime average would be a weighted average of those two sets of Trip A numbers.

mdmgso | 23 mai 2017

Ed D,

Something is way off. There is no way you should be limited to a 160 mile range with a 100kWh battery, even if you drive in ludicrous full time.

To achieve your EPA rated distance (315 miles), you need to average an energy consumption of somewhere around 30 kWh (30 kilowatts per hour).

Go to your Controls screen then to the Trips screen. Unless you have reset it, the bottom most trip (Trip C I think) should show your average average kWh consumption over the life of the car. What is it?

If you are around 30 kWh and your max range is only 160 (about one half of rated range) there is a big problem.

Whatever it shows, it's probably time for a trip to the Service Center (assuming you can get there).

Go to your Trips screen in Controls and look at Trip C which

Bighorn | 23 mai 2017

@mdmgso
You're confusing units and probably the OP. 300Wh/mile is probably what you were thinking. 30kWh is not 30 kilowatts per hour either, it's 30 kilowatt-hours. Maybe sit back and learn instead of teaching stuff that seems out of your wheelhouse.

ckcland2 | 23 mai 2017

That is odd, something is definitely off. I have documented a couple of trips now and I get really close to my rated range in my S60D. I average close to 95% of the rated range my car shows, so I tend to keep my buffer at 10-15%. My total avg wh/mi is about 310 or so. Please post your data points, especially your wh/mi, and some of the more experienced on here might be able to help.

Also, when you say Tesla "is not responding" what SvC are you calling? I have found my Devon, PA SvC to be extremely helpful.

tezzla.SoCal | 23 mai 2017

I've gone over 260 miles in my P85D (averaging around 70mph)

Tropopause | 23 mai 2017

Part of your discrepancy is the 10% range penalty for new ( <1,000 miles) tires, according to Tesla.

TesMD | 23 mai 2017

I think we are missing the key data points before we can say if something is wrong. We have not been provided wh/m as unshodbob requested. Till we see those numbers, can't say if anything is actually wrong. However, I do remember another person few years ago had same issue. His full rated miles would drop disproportionately in comparison to his wh/m and it was found to be a bad pack/cells.

Bighorn | 23 mai 2017

It also depends if these are cumulative mileages over time or a straight shot.

rxlawdude | 23 mai 2017

I'm skeptical of this, as the OP has been asked, at least twice, what his Wh/mi reading is (and it should be available for the car's "lifetime," if he hasn't reset Trip B.
Something's off about this.

UnshodBob | 23 mai 2017

@rxlawdude - that's strange, my lifetime wh/mile is stored in Trip A. I renamed it to "don't reset" so the reset button says "reset don't reset" :)

dknisely | 23 mai 2017

My bottom-of-the-barrel P60/75 averages about 330 kWh/mile, compared to 285 "rated," so that is 16% lower than rated. I believe I would get better if I didn't do all my driving around Seattle, which is both hilly and prone to lots of stop-and-go. I'm guess that with ~40% lower, you are some combination of a lead foot, someone who likes to to use the "P" and "D" parts of performance, live somewhere it is very hot, live somewhere it is very cold, or live somewhere that considers a mountain just a little hill. ;)

If you're getting that low of actual kWh/mileage when you drive on a relatively flat interstate with TACC or AP, gentle accelerator whenever you're in control, and <70 MPH, then you should talk to service to make sure there isn't something wrong.

BTW, for in-city Seattle driving, I get >500-550 kWh/mile, so even worse than you are seeing. Hills and stoplights every block are devastating. Cold weather also makes a HUGE HUGE difference.

Victorg-90D | 23 mai 2017

With Regen setting set to Standard, hills and stops should not matter a lot. My consumption was 320 Wh/m while learning to drive MS with Low Regen. After switching to Standard I get 280-290 Wh/m. We have enough stops and hills in our area, but maybe less that Seattle.

Tropopause | 23 mai 2017

rx has a good point. Where is OP?

Captain_Zap | 24 mai 2017

@dknisley

A good part of that consumption difference is caused by driving on very wet roads.

TesMD | 24 mai 2017

Guessing by the fact that we have not heard from OP, either he is a "spirited" driver with his wh/m in 400-450 range or this was more FUD.

UnshodBob | 24 mai 2017

@TesMD - FÜD for thought? :)

dknisely | 24 mai 2017

Yes, @Captain_Zap, I forgot to mention that. It has been improving now that the dry season has arrived.

trisailor33 | 9 juin 2017

Ed D: Another explanation for your situation is that the battery capacity is greatly diminished. I have a similar situation, I think, with my 2016 90D. The most that I can get is about 200 miles per 100% charge. The instruments keep telling me that I should be getting 270 miles or so. But no way.
Try this: check the trip page for the kwh used since last charge. Compare that to the percentage of battery used. So, for example, if you start your day with the battery 80% charged, and end the day with the battery 30% charged, you have used half of your battery capacity. Then look at the trip page for kwh used. If it were to say 36 kwh, then that would mean that your battery capacity is 72 kwh. (This is about what mine does, for example). I too have found the service folks to be unresponsive to this so far. "Your car and battery are behaving normally".