05' getting 40mpg if I'm lucky

i wanted to clarify a few things.

if you don't keep the 12v in great condition, the car will slowly charge it till it's full again. if you drain it every day by having your key fob in the car (even a small amount) it will start to slowly fail. when it does fail.. it will suddenly not start after a weekend of sitting.. or a day for that matter. you have a new battery so i'm not so worried about that issue.

EV battery & ICE... let's start with the initial startup process... when you walk out to your car, the key fob will notice you as you approach.. it turns on the interior lights and semi gets ready to do things. as you touch the door, it verifies your key fob again and unlocks... once you open the door, the thermos pump turns on and starts pumping warm coolant into your engine. (not sure how much power that takes) i think the brake compressor kicks on too to make sure you can use the brakes (just incase it's rolling and you're jumping in)... so.. you start the car. the 12v then flips a relay... the relay turns on the HV pack... the HV pack boots up the car... then the electric motors turn on and start rotation your engine at about 1100 rpms (somewhere around there.. maybe 1k)... then it's a process that can be deadly if you don't have fuel.. the fuel turns on and it test for ICE power... (it keeps trying if it doesn't start.. if you're out of fuel, it leads to is a dead hybrid battery)... so then the ICE is started. the hybrid battery still has to power you for a minute or so before any load is put on the ICE... so... if your battery is low (i've experienced this) your engine will shoot to what sounds like max rpms (i assume it's max ratio on the HSD) and it will take a few minutes to charge any bars.. at that time you probably damaged a cell or two or over rev an electric motor (just assumptions)

so.. the HV battery has a lot of work to do.. then once you're warmed up it still has to fill itself back up to a decent level and charge the 12v.

the 12v has no cakewalk either as it always has to run those pumps and such.. and it's always turning on lights when your key gets near the car (properly equipped cars)... if you ever walk up to the car and the unlock is a little slow.. and those pumps run slow... don't try starting it right away.. let everything settle.. give it a min.. then start... then replace the 12v battery (not really towards OP but anyone browsing this in general)

(i hope this is readable and makes sense)

 

That is milliamps of draw. Any car with a remote fob has the same parasitics.

Are you sure about this? I am fairly certain that the only mechanical things the 12v does while not in READY is prime the brake pump and click the 3 starter relays. So this is no draw.

Yes it primes the hydraulic (friction) brake pump. If it is already primed (shortly after using) then the current draw is minimal. If it has been sitting a very long time it can be up to 30A draw for a short time.

The 12v flicks a current limited relay for + VDC of the HV pack, then a ground relay. (Could be visa versa, I will have to check and verify). The third relay is the non-current limited +VDC line. It then de-energizes the current limited +VDC relay. So ON[1]-ON[2]-ON[3]-OFF[1].

Once the HV pack is online, the dc-dc kicks in and bucks the HV pack voltage to 14.5v if your 12v is low, and 13.8v if the 12v is healthy (13.8 needs to be checked).

then the electric motors turn on and start rotation your engine at about 1100 rpms (somewhere around there.. maybe 1k)... then it's a process that can be deadly if you don't have fuel.. the fuel turns on and it test for ICE power... (it keeps trying if it doesn't start.. if you're out of fuel, it leads to is a dead hybrid battery)... so then the ICE is started. the hybrid battery still has to power you for a minute or so before any load is put on the ICE...[/quote]

The ICE will power the car in the initial warmup period, but it will rely heavily on the HV pack. The goal is minimal ICE usage so it can get to temp nicely and cleanly.

The HSD when operating in normal operation will not damage or over-rev anything. It is impossible to hurt a Prius if in D and in READY. Overring usually occurs when dropping into neutral down a hill where before N the ICE was not spinning and during the neutral down-hill coast you get to speeds above 52mph. Then you will overrev the MG's. Damaging cells can only happen on the low end when you run force EV mode past the 40% low threshold with a functioning HSD.

[qutoe]
so.. the HV battery has a lot of work to do.. then once you're warmed up it still has to fill itself back up to a decent level and charge the 12v.

the 12v has no cakewalk either as it always has to run those pumps and such.. and it's always turning on lights when your key gets near the car (properly equipped cars)... if you ever walk up to the car and the unlock is a little slow.. and those pumps run slow... don't try starting it right away.. let everything settle.. give it a min.. then start... then replace the 12v battery (not really towards OP but anyone browsing this in general)

(i hope this is readable and makes sense)[/QUOTE]

The 12v battery does have a cakewalk. Lights, radio presets, SKS, are all a snooze-fest. The brake pump priming is the big drain but 30A is nothing compared to many hundreds of amps that cranking a traditional car needs.

Yes you can get the cell voltages, but you do not have the qualified skills or tools needed. If you go oldschool, then you must take the HV pack out (not hard, but dangerous if you do not know how to work around high voltage DC) and probe the cells with a multimeter. If you go newage, you hook up a CAN reader, solicit messages to the Battery control ECU (or hybrid ECU in a GenIII) and you get every cells internal voltage and calculated cell resistance.

 

It is 1 cell out of 168 that goes bad. That's all it takes, even though measurements are taken in groups of 12 cells. This triggers P0A80 and P3011-3028. There is no way to have a bad cell and not get a code. But a weak cell, likely your case, is not the same as a bad cell. In the absence of a code, Toyota will not get involved unless, apparently, there is a significant, repeatable drivability problem, such as the one detailed in that power loss on hill climb thread.

The at-home, DIY type can best test their battery in this way. Let the car sit for a few days. This causes any surface charge to dissipate, and a module with a bad cell has a much higher self-discharge rate. Then put the car in Ig-On (Power button twice, foot off brake, i.e. NOT READY!!!) and ask your ScanGauge or other tool to output the battery block high and low voltage. A battery in good condition will show a difference of less than 10 mV (0.010V) .

If you can get your car to redline at 45 mph going up I-17 from Camp Verde to Flagstaff, and your car is under warranty still, then you can start making a case for replacement.

 

O.K. geniuses, I pumped up my tires to 40/42 last night and now this morning I have a Master Warning Light on!... :hurt:

 

LMAO! You just can't win.

Since you do not have tire pressure sensors in your wheels the master warning light has nothing to do with adding air pressure.

 

Check your inverter coolant pump. See my instructions in your other thread.

 

master warning light... oh my... time to buy a scan-gauge... or have a local shop pull the code. get the code.. share it here.

since everything else you've done is technically preventive maintenance... maybe the real problem has just shown itself.

(i get low mpg too... i assumed a while back that the long times spent trying to charge my dead 12v battery may have caused issues with the charging system... totally an un-educated guess though.)

 

Checked the records, the ELECTRIC HYBRIDWATER PUMP was replaced in January.

 

Checked the reservoir as described, fluid is pumping as it should. MWL is still off...

 

Yes, the car is definitely prone to hesitation when the hv battery fan is running on high. Honestly, if you make it through this summer, you will probably make it to next spring, but I wouldn't count on making it any longer than that.

 

...heh heh, ain't that the truth.
I'm not so sure some of the Prius owners know that most cars these days have an 'average mpg' and mpg counter (computer). Even my '04 Caddy CTS has the same computer. Average, current, etc.

As far as the A/C goes. It's either 'ON' or 'OFF'. There is no 'MEDIUM'.
The LOW-HIGH' settings are the fan only, like any other car. The only appreciable overall settings that would make the pump possibly draw more juice/horsepower is the temperature setting. That being having the A/C longer to reach the lower temp.
I regularly turn the A/C button to 'OFF' in my '93 Volvo 4 banger when I need passing power...

 

I'm sure they do, however, on cars that get less than 30mpg the average may not change as drastically as the Prius because you are working with lower numbers. 5% on a 20mpg average doesn't look as drastic as 5% at 50mpg average. Obviously the 20mpg vehicle losses much more fuel with that 5% drop than does the 50mpg vehicle.

 

This is not true on a vehicle with a high voltage electric compressor. When first turned on, it will run on high. After a few minutes, the duty factor will scale down, ultimately reaching off, and cycling between a low setting and off if that is all it takes to meet demand.

That said, I do occasionally turn the A/C off in the Prius, when going up passes at interstate speeds and low SoC.

 

...I stand corrected...see, I'm a learner ...