DANGER: High Voltage!

Will your technicians be ready when the first hybrid rolls into your shop?

Are you ready for hybrids in your fleet? Well if you are not, or you just want some more information, read on. We will be covering what you need to know about servicing and maintaining hybrid vehicles. First, a word of caution! We need to start with safety, because we are dealing with high voltage.

Now don't fear, because if you follow basic safety rules, get some hybrid training and follow manufacturer recommendations, you will be safe. Every day utility companies work with high voltage without anyone being injured. When was the last time you heard that a utility worker was shocked or killed by high voltage? Most likely your answer will be never. The reason why is that utility workers are trained on how to work with high voltage and are provided with the proper equipment.

Work Smart - Work Safe! Remember: don't fear high voltage (HV)--respect it.


First, because we are dealing with vehicles whose wires carry lethal voltages and current capacity, we should be able to identify what kinds of wires we are dealing with.
• Low Voltage (Below 30V): RED or BLACK means these wires are safe to work with.
• Intermediate Voltage (Below 60V): BLUE or GREEN means you should take caution.
• High Voltage (Above 60V): ORANGE means that if you don't take precautions, that's all she wrote.

Second, avoid wearing metal objects when servicing hybrids. Remove jewelry, watches, phones--even your wedding ring. Better to have your spouse mad at you than be killed or hurt.

How is this so? Simple. Metal objects increase contact surface area and conduct current, thereby leaving us exposed to the dangers that come with electricity such as burns and electrocution. Furthermore, there are powerful magnets in hybrid components like the motor generators, and as we well know, metal is attracted to magnets.

Here are a few safety tips:
• Wear HV (1000V) gloves near ANY open connections
• Check gloves for pinholes by sending them out to a qualified tester
• Wear goggles to protect your eyes from sparks
• Be sure to have a yellow "rescue hook / pull pole." What's it for? It's an insulated hook / pole that is used to pull someone that is being electrocuted off the hybrid he is working on.
• Use a CAT III certified DVOM and leads on ALL cables and capacitors--other meters are not built to do the job.
• "Power down" before towing a damaged vehicle.
• Be sure to de-energize/shut down the high voltage system before servicing anything on this side of the vehicle. This is of paramount importance!
• Remember, high voltage orange or blue cables run under hybrid vehicles from their engine compartment to the rear of the vehicle. BE AWARE! Setting the lift wrong can do major damage to the HV system.

Precautions must be taken before attempting to diagnose or repair any component that has orange (or blue) wires connected to it. Remember the equipment that is needed: a CAT III meter and scope that is capable of handling 1,000 volts, correct vehicle information, 1,000-volt gloves with protective liners, and safety glasses.


Okay, so now that we know we should be wearing gloves and not haphazardly servicing a hybrid's electronics, let's discuss how we should disengage the high voltage (HV). Consult the information that can be found on the manufacturer's websites. Having a hard time remembering all those websites? If so, just go to www.nastf.org, on this site you will find links to all of the manufacturer's sites. The hybrid safety information is free. You should always disable the HV and wait five to ten minutes before working on ANY hybrid system electronics. Check the hybrid system with a DVOM to make sure voltage is at a safe level (about 12 volts).


Oil Changes: Every 3,000 to 5,000 miles, hybrids will require a run of the mill oil servicing with a proper oil type/weight. For customers with particularly high environmental concerns, recommend that they switch to fully synthetic oil, besides most hybrid recommend it. It will improve fuel economy and cut down on their necessary oil changes.

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