Hybrid Collision Repair: Safety First

"Read, read, read," advises Mike Schoonover of Schoonover Bodyworks Inc. in St. Paul, Minn. "Read anything and everything you can to learn more about the vehicle."

Schoonover's shop has repaired more than a dozen hybrids. "All of our techs attended the I-CAR hybrid class, which was very informative," he said. "We purchased the necessary tools and safety equipment and bought a toolbox that is strictly used for hybrid repairs." The toolbox contained electrical lineman's gloves, which Schoonover identified as the most important item (see "Hybrid Safety Tips").

Education is essential to safely and successfully repairing a hybrid car. Technicians must be able to identify a hybrid's key electrical components, which generally include a high-voltage, nickel metal hydride (NiMH) battery pack; a 12-volt auxiliary battery; high-voltage cables wrapped in orange insulation; a power control device or inverter and a service disconnect. Always consult the manufacturer's service manual when repairing a hybrid vehicle, as each model is slightly different.

It is important to keep the key off, out of the ignition switvh, and in a highly visible location such as on top of the dash board when a hybrid is in the shop.

Basic steps for disabling the HV system include the following:

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  First, make sure the ignition has been turned off and the key has been removed. This is important because a full hybrid runs on its silent electric motor when stopped and may appear to be turned off. Backup options include removing the IGCT Relay or the HV fuse under the hood.
  
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  Disconnect the 12-volt battery.
  
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  Wear 1000-volt Class 0-rated insulated rubber gloves and follow any special instructions provided in the service manual for disabling the high voltage system. Procedures may vary between vehicles and may include removing a service plug or removing a locking tab and flipping a switch.
  
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  Check orange cables for any current using a CAT III certified digital volt ohm meter (DVOM).
  

Orange cables indicate high voltage. On this 2004 Toyota Prius, the protective sheath is shown.

First, take care not to subject hybrids to high temperatures. "Turn down the heat of your spray booth, as NiMH batteries don't like heat," advised Craig Van Batenburg, AAM, owner of the Automotive Career Development Center. While technically, normal bake temperatures can be used with proper monitoring, Van Batenburg recommends keeping the temperature well under 140 degrees Fahrenheit. He also suggests painting all hybrids at the end of the day and allowing them to dry overnight.

A technician checks for the presence of voltage at the junction board terminals to the high-voltage battery after disabling the high-voltage system on a 2001 Honda Insight.

Hybrids can be jump-started according to manufacturer instructions. A dead high-voltage battery, however, is another story entirely.

A technician disables the high-volyage system in a 2004 Toyota Prius by pulling the service plug from the high-voltage battery. Notice he is wearing the high-voltage lineman's gloves while performing this important function.

Anyone who has worked on a Honda Insight knows that it differs from other hybrids in one important respect: its body panels are aluminum. More and more automakers are using aluminum and other lightweight material like plastic and laminated steel to improve fuel efficiency. While the Insight is the only aluminum-intensive hybrid currently on the market, aluminum is showing up in hoods, decklids, suspension parts and subframes everywhere.

Because of its unique properties, repairing this metal requires special techniques and equipment, such as a stud welder and an aluminum MIG welder. The equipment investment runs around $7,000 or $8,000, according to Mike West, collision chairman for ASA-Washington and owner of Southtowne Auto Rebuild Inc. in Tukwila, Wash. Which shops should learn to repair aluminum? Some say it's a question of cost/benefit, but West disagrees. "Everyone should know how to repair aluminum," he said. "Because Ford, Buick, Lincoln, Toyota, Honda all [use] some aluminum.

Knowledge is Key

Schoonover emphasized the importance of gathering information about any hybrid vehicle that arrives at the shop. "We download the most current hybrid information from I-CAR and the OEM Web sites," he said. "We also utilize data from trade Web sites and magazines.