Hybrid Fluid Service 101

Hybrid Fluid Service 101

Does the phrase ­"hybrid fluid maintenance" scare you? It shouldn’t. With more than 3 million hybrids on the road, and many of your customers ­considering purchasing one, servicing hybrid ­vehicles is in your future. Some special procedures must be followed when working on a hybrid.

Does the phrase ­“hybrid fluid maintenance” scare you? It shouldn’t. With more than 3 million hybrids on the road, and many of your customers ­considering purchasing one, servicing hybrid ­vehicles is in your future.
 

Some special procedures must be followed when working on a hybrid. Most dual-mode hybrids do not use a conventional starter attached to a bell housing. Instead, they use one of the motor/generators to start the engine. This allows the gas engine to start smoother and fast. During extended idling, like at stoplights, the engine will shut down. When the driver hits the gas, the electric motors will propel the car forward and start the engine if required. The hybrid system will also use the engine to charge the batteries and operate the cooling systems to reduce battery temperatures. 
 
This behavior can show up in the bay during service if certain precautions are not taken. The engine could start in the middle of an oil change, or the electrically driven A/C compressor could turn on during a recharge. 
 
Don’t take chances. Always check the service information for the disable procedures. Some vehicles may require that the key be a certain distance from the vehicle. Others may require a scan tool to disable certain functions. Never assume that one model year of a hybrid is the same as the next. Many manufacturers made sweeping changes due to improvements in software and hardware.   

Engine Oil
Oil changes may not be needed as often with a hybrid because the engine runs less during low speeds and stop-and-go driving, but the oil still needs to be changed (refer to the vehicle manufacturers’ oil change interval recommendations).
 
Always use premium engine oils for these vehicles. Some late-model hybrids call for 0W-20 or 5W-20 weight motor oil. Not using the correct weight will damage the top-end of the motor.
 
Starting an engine is the greatest cause of wear on any engine, and hybrids regularly shut down and restart the engine more than a conventional vehicle. 
Transmission Fluids
In all hybrid automatic transmissions, transmission fluid does not come in contact with the motor drives. On the Prius, the CVT part of the transmission is sandwiched between the two motor/generators. In the first generation Prius, there were rare reports of the transmission fluid leaking into the electric motor case and damaging insulation. Any leak or loss of fluid should be taken seriously. 
 
Some models will require a CVT-specific transmission fluid, while others will require a specific grade of fluid that could be compatible with conventional transmission fluid specifications. 
 
Pay attention to the Mercon and manufacturer grades. For example, Mercon V is not the same as Mercon LV, which has a different viscosity. Check the container or ask your supplier if a fluid is compatible before you put it in the transmission. Never take specifications for granted — some Ford Fusion hybrids call for a Toyota/Aisin grade of transmission fluid.

Cooling Systems
Most hybrids have a separate cooling system for the inverter and electric motors/generators in the transmission case. These typically have their own electric pump, heat exchanger and special coolant. On the Fusion, Escape and Prius, there are two coolant reservoirs under the hood.
 
Always make sure the fluid is at the correct level. Most ­manufacturers recommend flushing and filling the system when the engine’s cooling ­system is serviced.
Power Steering
Bad news: Hybrids do not have conventional hydraulically assisted power steering due to the requirement that the system needs to operate with the engine off. The GM full-sized pickup and SUV two-mode hybrids use 42-volts from the battery packs to power the rack. 
Air Conditioning
Some hybrid vehicles use air conditioning compressors that are operated by an electric motor instead of a drive belt. The motor’s insulated windings are immersed in the compressor’s lubricating oil. The oils used in these compressors have high dielectric (non-conductive) properties. 
 
If a different type of oil somehow makes its way into one of these compressors, and if the insulation on the windings is damaged or compromised, a variety of problems may occur.
 
The greatest risk is that the oil may conduct high voltage to the compressor case or connected components. A person may receive an electric shock if they touch the compressor, engine, etc., and an appropriate ground.
 
On the second and third generation Civic Hybrids, a combination belt/electric drive and A/C compressor is used and requires a special insulating compressor oil: Sanden SE-10Y (P/N 38899-RCJ-A01).
 
The A/C compressor works in conjunction with the engine’s idle stop system to keep the A/C going if the engine shuts off when the vehicle is stopped. Normally, the engine stop system will kill the engine momentarily when the vehicle comes to a halt after being ­driven at 7 mph or faster. 

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A Show of Changes

TechShop was on site in Orlando, FL for the Matco Tools Expo and the Mac Tools Tool Fair.

To be successful as an auto technician, you have to keep up with the changes. Technology moves fast, and the cars you all work on are always changing. Just as fast, the tools and equipment required to do your job are changing right alongside.If you’re thinking about new screwdrivers, you’re right. But that’s only a part of it. As the spring season approaches every year, the tool companies that cater to our industry kick off the weather we’ve all been waiting for with their annual tool shows to highlight the latest technology that’ll soon be hitching a ride on your local tool truck.To keep up with it all, TechShop was on site in Orlando, FL for the Matco Tools Expo and the Mac Tools Tool Fair. There were new screwdrivers and new colors. There were also new sockets, lights, toolboxes, storage options, electronics, diagnostics and more. And in addition to the new tools that are born with new technology, it always amazes me to see all the new tool solutions made, simply to make a technician’s job easier!Reflecting some other big changes in the tool industry is the other part of it, and those changes are a shift in manufacturing and sustainability. A theme which I’ve unintentionally followed this year in my columns is accepting essential aspects needed to succeed in our industry. One of those is adopting eco-friendly practices in our shops. I was pleased to learn that the tool industry has their eye on these aspects as well.Why is it so important? The automotive repair industry is building a new initiative where every oil change, every part replacement, every repair and the equipment, tools and supplies we use on a daily basis all have an eye toward sustainability. I don’t feel it’s a matter of choice; it’s a responsibility we all owe to our environment and future generations.Made in the U.S.A. That’s becoming a common theme that is resounding with tool manufacturers. We all know the importance of supporting our own economy, and the shift to U.S. manufacturing is starting to gain a foothold, bringing with it another advantage: sustainability in manufacturing.Bringing manufacturing back to the U.S. gives company engineers the ability to closely manage manufacturing processes, ensuring they are not only economically sound, but have minimum negative environmental impacts while conserving energy and natural resources.I should be clear, this isn’t to say that manufacturing abroad is bad, or that it’s harmful to the environment. Some of that takes place here. But in addition to engineering the latest technology in tools, it’s a good feeling to know that the companies we support as technicians are beginning to make a shift, with the best interest of our economy and the future of our environment at the top of their list.By supporting suppliers and manufacturers of products who share our commitment to the environment, we can amplify the impact of everyone’s collective efforts and contribute to a greener automotive ecosystem.As far as the new tools, we’ll keep the information coming your way. TS

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