Hybrids bring new opportunities

Although hybrid vehicles currently represent only around 3.5 percent of new car sales, that number is expected to increase consistently in the coming years.


Although hybrid vehicles currently represent only around 3.5 percent of new car sales, that number is expected to increase consistently in the coming years. That percentage could really explode if fuel prices spike like they did in July 2008. So, whether it’s sooner or later, you’ll eventually need to perform service on a hybrid vehicle.

What basic precautions should I be aware of when servicing a hybrid vehicle?

Let’s start by putting things in the proper perspective. While it’s true that hybrid technology has some new twists when it comes to service, you needn’t panic. For the most part, hybrid vehicles require many of the same services as conventional vehicles. This means most routine services such as oil changes, wheel alignments, brakes, and suspension and exhaust work are pretty much the same as on regular cars. The biggest difference lies in the electrical system, where hybrids have some distinct differences.

Typically, hybrid vehicles use two separate electrical systems. One of these systems incorporates the standard, 12-volt electrical components found in most vehicles. The other electrical system employs the use of high voltage for the hybrid drive. The required voltage for hybrid drive operation can exceed 600 volts. Use extreme caution around any part of the high-voltage system. If not, you could be injured or killed. You can indentify the high-voltage system by warning labels and the bright orange color of the high-voltage cables. Make sure you receive proper training before attempting to service any part of the high-voltage electrical system and its associated hybrid drive. You should also wear appropriate personal protection equipment, such as high-voltage insulated safety gloves and a face shield, when working around the high-voltage system.

Can I use the same digital multimeter (DMM) on a hybrid’s high-voltage electrical system that I’ve always used for other automotive applications?

Absolutely not! Because of the inherent high voltages in the hybrid drive system, you will need to use a meter that meets a standard known as CAT III. This also applies to the meter’s leads. A meter meeting this standard offers the best personal protection when working around the electrical energy potential found in high-voltage hybrid drive systems. By comparison, a standard DMM only meets CAT I or CAT II requirements. Finally, even though a CAT III meter is the right one for the job, it cannot keep you safe by itself. You should only use a CAT III DMM in conjunction with the proper training and personal protection equipment.

Are any special tools required for servicing high-voltage components?

Yes, insulated socket and extension sets are available for additional safety when removing components such as the high-voltage batteries and other key parts.

Will a scan tool help in performing diagnostics on a hybrid vehicle?

Yes, but it really depends on the specific scan tool you’re using. All hybrids incorporate diagnostics into their OBDII system. A vehicle-manufacturer-specific, factory scan tool provides the most comprehensive functionality for hybrid diagnostics, but some aftermarket scan tools can perform some functions. With that said, check with the provider of your current or prospective scan tool to see what kind of coverage it has now, and what’s on the horizon. Since hybrid technology is evolving so rapidly, and so are scan tools, new applications are being released on a regular basis. It may be wise to ask around to see what other techs are using for hybrid scan tools.

What kind of equipment do I use to charge the hybrid drive batteries in a hybrid vehicle?

First of all, let’s make one thing clear: NEVER, EVER attempt to charge the high-voltage batteries in a hybrid vehicle! Not only is it dangerous, it’s unnecessary. Once again, the high-voltage electrical system is clearly identified through the use of warning labels and bright orange cables, so beware!

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