What are the definitions of some of the acronyms that appear at this site?
How do I improve my mileage?
- ICE is Internal Combustion Engine
- DINO (or dino) oil is non-synthetic oil, the stuff that came from dinosaurs (get it? )
- FE is Fuel Economy
- ECO is the ECO Switch (hidden to the left of the driver's left knee) that sets the Air Conditioning system to economy mode.
- SOC is State of Charge
- MFD is Multi Function Display (it's found inside your speedometer or on your NAV system)
- NAV is Navigation System
- HSD is Hybrid Synergy Drive (Toyota's name for the hybrid system)
- TCH is Toyota Camry Hybrid
- ECU is the Engine Control Unit. This is the computer "brain" for the entire Toyota Hybrid Synergy Drive system (HSD) and controls all of the energy utilization and recovery.
- MG1 is the smaller motor generator mechanically connected to the Power Split Device (PSD) sun gear. It is utilized by the Engine Control Unit to provide what is the equivalent of a "gear ratio" for the Toyota Hybrid Synergy Drive system (HSD).
- MG2 is the larger motor generator mechanically connected to the driven axle (axles in the Hylander AWD) and the Power Split Device (PSD) ring gear. It is utilized by the Engine Control Unit for electrically driving the vehicle, assisted electric power for the ICE when required and for recovery of excess energy when coasting and braking, sometime called regenerative energy or simply regen.
- PSD is the power split device -- it replaces the transmission in the Toyota Hybrid Synergy Drive system (HSD). Look here to see how it works.
- Factors not related to the way the driver operates the vehicle.
Your mileage will increase...
- ...after your first oil change.
- ...when the weather is warm. In cold weather the ICE needs to run to warm up.
- ...if you drive on flat roads
- ...when the air conditioner or heater is set to off
- ...if you increase tire pressure. The trade off is a noisier and possible more uncomfortable drive. Always stay within the posted recommended pressure range set by the manufacturer. See this survey to see how other drivers set their pressure.
- ...if you use top tier gas
- ...if you switch to Low Rolling Resistance tires
- Factors related to the way the driver operates the vehicle.
- After the engine warms up, come to a complete stop for a few seconds and see if the engine turns off after 4-5 seconds (not after one second). When it does this you are now in EV mode. The car will drive 'in the blue', on battery power, up to 40 MPH. Please see how-come-i-cant-go-into-ev-mode-sometimes (the third post) for an explanation.
- Combine trips and make your lengthiest trip the first leg of your trip. This will give the car a chance to warm up.
- Don't store heavy items in the trunk or travel with passengers. Three extra adults in the car could add between 400 and 600 pounds.
- Don't warm up the car before driving. Power it on and when you see READY, put it in gear and go. This is not practical if you live in a cold climate.
- Try and drive at a constant speed. Frequent stops and starts hurt mileage.
- Pulse and Glide Accelerate to a nice speed, say 65 MPH and then let the car glide down to 55 MPH (traffic permitting) and then start the process up again
- Anticipate traffic light changes and glide up to the light, rather than using the gas and braking
- Use cruise control when on flat roads.
- Avoid jack rabbit starts
- Avoid bumper to bumper traffic, if possible
- Monitor the battery's charge level and avoid letting the it run low when in traffic (the ICE will turn on at slow speeds to help regenerate the battery). Try and leave a gap between you and the car in front of you and then pulse and glide to try and regenerate the battery.
- There are many other driving techniques that people use to increase their mileage. There are quite a few posts and threads that discuss this topic. Some of the techniques you will see could potentially put the driver, passengers and others at risk. Please use common sense and observe local traffic laws as well as proper driving etiquette when considering whether some of these tactics are appropriate for you. The EMT in the ambulance will not ask you what your mileage was before the accident. Always drive safely!
- Can the battery be jumped?
- Yes, the small 12 volt battery (located in the trunk) can.
- The hybrid battery can only be jumped by the dealer.
- Before attempting to jump the battery, please read the manual to make sure you know what you are doing.
- You should NOT try and jump start another car.
- Are you sure I can't jump another car? I asked the dealer about this prior to buying the car, and they said it would be okay.
- A.The 12-volt battery in the TCH is an AGM (Absorptive Glass Mat) type. These batteries are designed to survive repeated deep discharge/recharge cycles without failure, but cannot take rapid charge or discharge without potential damage (temperature dependent). The TCH's ECU circuitry limits the charge/discharge rates. Jump starting another vehicle using the TCH's 12-V battery is likely to reduce its service life appreciably due to the very high cranking current that is drawn from it in such an operation. (It's also a rather expensive battery to replace! It incorporates both a temperature sensor and a gas venting valve and gas discharge attachment.)
- Does the 12V power outlet plugs inside the car stay on when the car is powered off?
- No, these are disabled when the car's power is off.
- Can I change the settings for the headlight auto off timer?
- No, you can't, but the dealer can. For a list of the options that the dealer can modify, please see the PDF attached to this link.
- Do the rear personal reading lights (only available in cars with the moon roof) turn off after a period of time?
- Even though the interior lights go off after a few seconds, the rear personal reading lights do not turn off when you power off the car. Please make sure these lights are turned off as they can drain your battery.
- What is the maximum speed I can achieve on battery only?
- When the engine is warmed up you should be able to get up to 40 MPH. This will vary due to a number of conditions. Eventually, the battery charge will drop and the ICE will turn on to help regenerate power.
- What happens if I run out of gas?
- When your gas gauge reaches E and your MFD indicate 0 miles left on the tank, you have approximately 3 gallons of gas left in the tank. You should try and refill your tank as soon as possible. There are no awards given for the most mileage driven per tank, similarly, it's not fun standing on the side of the road hoping someone will give you a ride to the nearest gas station.
However, in the unlikely situation that you forgot to refill your tank, you failed to notice the dashboard warning light and the car ran out of fuel, your car will be able to drive approximately one or two miles (depending on driving habits, conditions, and battery state) before the main hybrid (traction) battery runs out of power. If you are unable to make it to a gas station before the hybrid battery dies, your car will be stranded and you will need to contact the Toyota dealership to have the battery charged.
Word to the wise...when the warning light tells you you need fuel, get it.
Why do my brakes shudder during the first few stops?
Where can I learn more about the car and hybrid driving techniques?
- Due to the nature of a hybrid vehicle, there are points in time when you may be applying the brakes without actually using the brake pads. This is called regenerative braking; which uses the HSD to slow the vehicle. Since the brake pads are not used as often as in a non-hybrid vehicle, moisture can build up on the pads and rotors. If moisture is present, the pads may "slip" causing your brakes to shudder while applying them. This will happen until the moisture is burned off. If this happens frequently, during more than the first few stops, you should consider contacting your service center.
- How accurate are the dashboard calculations?
- Typically the MPG displayed is 1-1.5 MPG high. The fuel usage is an approximation, so it would be difficult to calculate an accurate MPG.
- The speedometer is approximately 3 miles per hour high at 60 miles per hour (see this post for details)
- What mileage are other drivers getting?
- This page lists the various users mileage. Please don't expect to be able to achieve the mileage that some users are posting. You may not be able to, nor want to, drive under the conditions that they did to achieve these results.
- How do I interpret the graph on the ECO Drive Display (one of the screens inside the speedometer) and the blue rings that, at times, appear around the speedometer?
How do I know if my car is turned off properly?
- The ECO Drive chart shows the car's approximate average mpg since you last started the car (it resets every time you turn the car off). It is a stair step display and is updated every 10 seconds.
The rings may appear on the outside of the speedometer as your mpg improves. The gauges change luminosity and more rings are added at the same time as the ECO Drive stair step increases. The following are the levels of the stair steps and corresponding blue speedometer rings:
When you turn off the the car, the ECO Drive display (MFD) retains the ECO display for 3 seconds. It will display "EXCELLENT" if your average was 36 MPG or more. Remember, these are approximations of your mileage.
- Level 0 -- Below 25 mpg -- Ring brightness off, no lines
- Level 1 -- Between 26 & 30 mpg -- Ring brightness is subtle with one thin blue line
- Level 2 -- Between 31 & 35 mpg -- Ring brightness is medium intensity with thicker blue lines
- Level 3 -- 36 mpg & above -- Ring brightness is full intensity with the thickest blue lines
The ECO display on the dash is not related to the ECO switch next to the tank refill switch referred to in this post.
- Look at the clock on your dashboard. If it's on, your car is on. If it's off, the car is off.
Are there any hidden diagnostics menus (NAV users only)?
How do I install...
- Debug mode:
"There's a fun debug / diagnostic mode available in the NAV. Hold down the INFO button then cycle the headlights on, off, on, off, on, off then let go of the INFO button."
- Display screen hidden menu:
There is an hidden display screen menu. To access this menu, see this post.
- Override menu and other diagnostics:
If you have NAV disc 5.1 or a hacked version of a later disc, you may access the navigation lockout override by:
(menu screen appears)
(volume screen appears)
Press upper left corner
Press lower left corner
Press upper left corner
Press lower left corner
(Service Menu will appear)"
Questions regarding changing fluids and filters
- ...a backup camera?
- For instructions on installing a backup camera (with pictures), see this post.
- ...a heater block?
- For instructions on installing a heater block (with pictures), see this post.
I do not like the look of those hybrid badges. Should I remove them? How can I remove them?
- Where can I learn more about engine oil
- Is there a way to make changing oil less messy?
- Yes! Install a quick drain oil valve -- they work great. Visit the YM International Web site to purchase the part.
- Why is my oil filter on so tight?
- If this is your first oil change, the filter will be on extremely tight. This is because Toyota dealerships use an air gun to screw in the filter. This makes it difficult to get off and often requires you to take it to a shop.
Tips for attempting the removal yourself:
- Before starting your oil change, make sure you have an oil filter wrench that fits the TCH filter.
- Before attempting to remove the filter, remove the black plastic splash guard below the filter location. This will allow you to access the filter with both hands.
- What oil and filter should I use?
- This question has been asked many times, and, there is no one answer. Many people have used a traditional oil (dino) 5w-20 (could also purchase a synthetic flavor), while others use a full synthetic 0w-20. See 5W-20 or 0W-20??? for further discussion. Click here to see the results of a survey on oil grade choice.
As far as the oil filter is concerned, there has been less discussion on this topic. Some have noted that Purolator might manufacture the Toyota filters and feel they are the best choice.
- How much should my oil change cost?
- These are rough estimates and should not be used for exact pricing guidance.
If you have your oil changed...
- ... at your dealer, the price will be between $25 and $75, depending on the type of oil you choose to use. Some people have reported dealerships charging close to $100 for synthetic oil.
- ...at a local shop, the price will be between $25 and $50, depending on the type of oil you choose to use.
- ...by yourself, the price will drop to between $20 and $40, depending on the type of oil you choose to use.
- What are the recommended engine and transaxle coolant change intervals?
- For information about recommended engine and transaxle coolant change intervals, see this post
- How do I remove the air filter?
- For instructions on removing the air filter (with pictures), see this post.
- Improper removal might lead to paint damage. Perform this process at your own risk. The original poster and others in forum are not responsible for any damages.
Removal of the hybrid badges, located above both front wheel wells and on the trunk lid, has been debated concerning the safety of emergency response personnel. Some feel the removal of these badges could lead emergency response personnel to believe the vehicle is a non-hybrid thus putting them in harms way. Others feel emergency response personnel are trained to deal with hybrids and their tactics would not put them in harms way regardless of whether or not the vehicle is a hybrid. (My two cents...I think it unwise to potentially put someone else at risk just for the appearance of your car. You bought a hybrid, be proud of it!) If you feel conformable with the potential safety issue, and would like to remove the badges, you might do so with little effort.
Removal of the badges is easiest during warm weather and when you first get the car. The badges are held on by a soft adhesive. To remove this adhesive, use dental floss in a saw-like motion starting at one corner and slowly working your way to the opposite corner. If the adhesive is difficult to cut through, you may try slightly heating the area with a blow dryer.
After the badge has been taken off, the rest of the adhesive can be removed by rubbing your finger around the area creating a ball of adhesive. Again, this works best when the metal is warm.
My car acts differently when it first starts up and when it is warmed up, are there different stages?
What mode is best for mpg?
The following statements currently hold true regarding the modes:
- The warm up times vary with the temperature as well as use of the car's climate control system. The ECO mode helps, but if the temperature is below 40F, you may see the ICE stay running for a long time if you have the heat on.
The TCH has 4 stages of operation.
Remember, cold weather conditions and turning on the heater may prevent the ICE from stopping (but it will keep you warm, use your own discretion and common sense).
- Stage 1 is initial warmup. The ICE will not shut off and battery assist is greater than normal. In warmer weather, this lasts a minute or less. In colder weather it can last a few minutes.
- Stage 2 is engine warmup. It lasts 2 or 3 miles in cool weather, longer in cold weather. The ICE shuts off if you stop, but will not shut off when coasting.
- Stage 3 is partial hybrid mode. The ICE is warm, and the engine shuts off if you coast between 35 and 41mph. If you stop with the ICE running, it will stop after a short time, but stays running once started until you coast (between 35 and 41mph) or stop again.
- Stage 4 is full hybrid mode. Enter it by braking to a complete stop (or slowing to a speed below 5 miles per hour) for approximately 7 -10 seconds (until the ICE shuts off), it is possible to enter Stage 4. It is hard to know if this ICE shutdown is due to stage 3 or entering stage 4. The only way to know is to accelerate to ~20mph and coast.
If the ICE...
In stop and go traffic, stage 4 lets the ICE stop any time you coast, instead of having to be over 35mph when coasting. If the ICE is running, turn off the heat and the ICE turns off, you'll know that you are in stage 4.
- ...continues to run after you stop the car, it is still in stage 3.
- ...stops within a few seconds the car is in stage 4.
If you want to try and force stage 4, the ICE must be running when you stop or the TCH will not enter stage 4, it will remain in stage 3. You can hold your foot on the brake and "blip" the throttle to "start" the ICE, and then enter Stage 4 after it shuts down (~ 7 seconds.)
- Typically how long do the stages last?
- Assuming moderate (50 to 60F) temperatures when driving on suburban roads (between 25 to 40 miles per hour)...
Of course, warmer temps reduce the Stage 2 and 3 times and colder temps can greatly increase them.
- Stage 1 lasts approximately 30 seconds
- Stage 2 approximately 3 minutes
- Stage 3 approximately 3 minutes
The modes are, except for the A/C-heater performance, in essence "psychological" ways to help the driver get the best FE, by affecting the way he/she accelerates the car to a certain speed.
Looking at the modes from this perspective, one could therefore say that:
- the same amount of power is available in all 3 modes, e.g. kick-down will provide the same performance in all 3 modes (there is a video showing exactly this here, where also a chart shows the gas pedal throttle response in all 3 modes); at constant speed the modes do not make any difference in the performance of the car (expect the A/C-heater changes in ECO mode, that might improve FE since less energy is required to keep the cabin at a set temperature)
- the fuel consumption might not be affected by using the 3 modes - fuel efficiency is greatly dependent on how one accelerates, traffic, type of roads, temperature, etc.; there are users on Prischat.com that claim very good fuel efficiency in PWR mode, others that cannot get a good fuel efficiency at all in PWR mode
- there are no measurements or objective tests/results showing that keeping always the same mode has any effect on the lifetime of the car as whole or on the battery/hybrid drivetrain
- there are no measurements or objective tests/results showing that the 3 modes have any effect on the way the cruise control responds to changes in road inclines
- there are no measurements or objective tests/results showing that changing the modes will change: the steering wheel response; the maximum voltage allowed on MG2 in ECO mode (e.g. 500V instead of 650V; there is such a claim for the Lexus CT200h, that shares the same drivetrain as the Prius Gen 3, between ECO/normal mode and Sport (PWR) mode); the ICE management (e.g. changes in the valve opening times, etc.) or the way the ECU provides current to MG2 (i.e. more in PWR/less in ECO) for the same acceleration/power request (same HSI bar length)
How to know when hybrid battery is failing
What causes hybrid batteries to degrade and fail?
- ECO mode is better suited for stop&go city traffic, where frequent stops and accelerations could lower FE if the driver accelerates aggressively (due to personal style, or traffic flow) several times in a row in short trips
- Normal mode is best suited for suburban driving with less traffic and stop&go situations, as well as for highway; good to excellent FE might be achieved in city traffic if a light foot is used, traffic flow allows for slower accelerations and temperatures do not force the ICE to be on longer than necessary to keep the battery charged;
- PWR mode is perfect to get with less "psychological" effort (i.e. no need to "stomp" on the gas pedal) more responsiveness from the drive train on winding-mountain roads (e.g. more fun drive), merging on an highway quickly without feeling that you need to kick down to get to speed, to get quicker overall response by keeping the ICE on more often
Eventually all batteries will fail. Hybrid Electric Vehicle (HEV) NiMh batteries have a life cycle. When the hybrid battery does not last as long as the rest of the vehicle, replacing it costs several thousand dollars and creates hazardous environmental waste. Delaying battery failure beyond the service life of the vehicle will reduce the negative environmental impact of hybrid vehicle ownership and save the vehicle owner thousands of dollars.
This graph depicts the typical life cycle of a Hybrid Electric Vehicle (HEV) hybrid battery:
There are three major phases of hybrid battery lifespan. Usable capacity and performance decreasing as the battery ages:
Typically begins: Typically ends: Phase 1: Healthy hybrid battery New Vehicle 3-6 years Phase 2: Weakened/weakening hybrid battery 3-6 years 5-11 years Phase 3: "Failed" hybrid battery (DTC code present) 5-11 years
Each hybrid battery 'pack' is comprised of many individual battery cells. Consumer hybrid electric vehicles have anywhere from 120 to 240 individual battery cells. Each cell is about the size of a typical D cell battery. At the beginning of the hybrid battery’s life, each cell easily provides all of the energy needed to propel the vehicle and to stay in sync with other cells in the battery pack. As time progresses, the battery will start to degrade and the cells will fall out of sync with each other. Results of this degradation include:
(1) usable cell capacity is reduced
(2) cells drift out of balance with each other (voltage delta).
The speed of this deterioration is determined by a variety of factors, including vehicle make/model, climate, driving habits, variation in battery cell construction, and more.
This battery deterioration means that the individual cells within the battery pack can have a different charge level and capacity - they are no longer 'in sync' with each other. Some cells can be 'full' while other cells in the same battery pack are 'empty'. The overall battery pack performance is limited by the vehicle's battery management system to the weakest cell when discharging and the strongest cell while charging. As a result, the wider the cell imbalance, the narrower the usable range of the hybrid battery becomes. The car's battery management system uses only a limited range of the battery cells actual physical capacity (80%-40% for Toyota and 80%-20% for Honda). As the usable capacity decreases and the cells become further and further out of balance with each other, the vehicle us able to use less and less of the batteries actual capacity. The vehicle cannot correct this imbalance problem on its own. The car cannot force the cells back into balance with each other.
If no attention is given to the hybrid battery, it will 'fail' and the check engine light/hybrid battery light will be illuminated.
How do I know if my hybrid battery is failing?
There are several subtle cues displayed by a hybrid vehicle that can alert you to degrading hybrid battery capacity & performance. If not acted upon, the battery will ultimately display a fault code for battery 'failure'. By paying attention to the warning signs and performing preventative care on the battery before it 'fails', you can easily improve battery health and prolong its life. Prolong Battery Systems will improve hybrid battery performance, save you thousands of dollars in avoided replacement hybrid battery costs, and benefit the environment by requiring one less hybrid battery to be manufactured. (Note: The symptoms described below are applicable to Toyota vehicles. Honda vehicles display similar symptoms. Feel free to give us a call and we can describe the Honda symptoms for you.)
The first indication
of decreased battery performance is a reduction on fuel economy and diminished vehicle performance. The vehicle does not get the same fuel mileage that it used to and it feels sluggish - lacking in power during acceleration. If equipped, EV mode may be less frequent and for shorter duration then when the vehicle was newer. This happens because as the hybrid battery weakens, the vehicle is forced to use less of the battery and more of the gas engine. It also spends more time charging the hybrid battery in the background (i.e. not shown on the dash). Both of these behaviors reduce fuel economy. This can last for several months as the battery weakens and fuel economy/performance progressively decreases. Note: sometimes under inflated tires can cause similar symptoms. We recommend checking your tire pressure to be sure that is not the cause of decreased fuel economy.
The second warning
that your hybrid battery is failing is called negative battery recalibrations. This is initially seen when parking the car for a few days (such as over a weekend) or when parking the vehicle overnight. Just before the vehicle is parked, the dash battery display shows a full or near full hybrid battery. When the car is started the next morning (or a few mornings later) the battery display shows an empty or near empty battery. The empty battery indication can be displayed immediately when the car is started or drop from full to empty in the first few minutes of operating the vehicle. This occurs most often in warmer climates or seasons, but as the battery degrades will happen in any climate. This is a clear sign of a weak battery that needs attention soon. If ignored, the battery will soon progress to the point of failure. If treated with Prolong Battery Systems before the battery degrades further, the success rate for recovering the pack and restoring it to good operating condition is nearly 100%.
The third and final warning
the vehicle displays of a failing hybrid battery is negative recalibrations that occur while the vehicle is being operated. These recalibrations often occurs on warm days or when idling the vehicle for longer periods (such as waiting for a parking spot or railroad crossing), but as the battery weakens can happen at any time. These are seen as the dashboard battery charge display suddenly dropping from near full to near empty. This drop is followed by the gasoline engine revving to a higher than normal idle speed while force charging the battery from empty to full. This event is easily visible on the dashboard battery display and can be audibly heard by the loud, unusual high idling of the gasoline engine. This can be very unsettling behavior as the vehicle seems to ‘take over’ and ignore driver inputs while force re-charging the battery. This is a red flag, serious battery issues are imminent.
In these cases, we strongly recommend using the Prolong Battery Reconditioning Package to perform a preventative battery reconditioning as soon as possible. Ignoring these symptoms for more than a few weeks will result in the battery displaying a failure code and being stranded on the side of the road. If treated with Prolong Battery Systems as soon as these symptoms become present, the success rate for recovering the pack and restoring it to good operating condition is nearly 90%.
The next phase of battery failure is a failure light on the dash and cell failure. Our products can still help vehicle owners in this situation, but the success rate depends on how long it has been since the failure first appeared. If this describes your car, please give us a call to discuss your specific situation and learn how much our products can help you and your hybrid vehicle battery.