Article and photos by Jason Emery
First released in the 2007 model year, the Nissan Altima Hybrid is entering its third year on the market. Its hybrid technology is based on that of the Toyota Camry model. The vehicle’s design has changed very little over the last three years, so the response procedures and the location of key components has remained consistent.
Vehicle Identification
The physical design of the Altima Hybrid is exactly the same as the nonhybrid version. Responders must look for the external hybrid badging found on the both front doors (photo 1) and on the right side of the trunk lid (photo 2). Responders should also look at the rear “deck” area behind the rear seat for the battery cooling vent (photo 3) located between the rear speakers, which is found only on the hybrid model. Additionally, if the fourth alphanumeric character in the vehicle identification number (VIN) is a “C,” the vehicle is a hybrid.
Internal indicators are also present in the instrument panel/dashboard area. In the hybrid, a gauge measuring kilowatts (“kw”) replaces the tachometer (photo 4). On the instrument panel, you may also see a “ready” light, indicating that the vehicle is ready to move at any moment, even if the gasoline engine is shut down. Additional indicators in the engine compartment include orange wiring, high-voltage warning labels, and the hybrid logo on the plastic engine cowling (photo 5).
Hybrid Systems and Operation
The Nissan Altima Hybrid uses a 245-volt high-voltage battery for its electrical power storage. The battery is comprised of 34 low-voltage (7.2-volt) modules connected in series. These are dry-cell batteries and do not pose a leak hazard. The high-voltage battery is located directly behind the rear seat. As with other hybrids, the battery is recharged through regenerative braking and from power from the gasoline engine.
This model is a “full hybrid” since it runs solely on its electric motor at lower speeds and also uses the electric motor to assist the gasoline engine, depending on the acceleration needs. This model uses both direct (DC) and alternating (AC) current in its hybrid system. The 245-volt DC the battery provides is stepped up to 650 volts AC to power the electric motor, using an inverter unit located close to the electric motor that is found in the transaxle. The vehicle’s electric power steering (EPS) system functions off a stepped-down 42-volt DC system.
Response Considerations
Controlling Hazards
To avoid the vehicle’s potential travel path, responders must always approach a vehicle involved in an accident from the sides, not from the front or rear. This is especially important for hybrid vehicles incidents, in which the engine may seem to be off, but could simply be in “ready” mode, which would allow it to move with no warning if the driver were to take his foot off the brake or inadvertently hit the accelerator. Secure the vehicle from possible movement by shifting transmission into Park and engaging the parking brake, if possible. If the vehicle’s damage prevents the options above, chock the wheels to prevent movement.
The next step in securing the vehicle and preventing its movement is to disengage the high-voltage and occupant protection systems by turning off the ignition (button on dash) (photo 6) and disconnecting the negative cable from the 12-volt battery. In this model, the 12-volt battery is located in the truck on the passenger side (photo 7). This action removes the 12-volt power from the normally open relays in the high-voltage system, thereby shutting down the flow of high-voltage electricity. The estimated bleed-down time for the high-voltage system is approximately 10 minutes. The occupant protection systems may remain active for up to three minutes after disconnecting the 12-volt battery.
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If the situation requires it, for additional protection, use the service disconnect mounted on the battery, which is located in the back wall of the trunk towards the passenger’s side behind a small panel (photo 8). Once the lever is accessed, simply pull up and rotate it down towards you, and then straight out (photo 9). This severs the connection between the battery and the rest of the high-voltage system. The battery, however, will remain energized. If the battery is damaged, do not attempt to access the service disconnect lever. In that case, only a trained technician with the proper equipment should attempt to do so.
Extrication Operations
There are no specific techniques for extrications involving the Altima Hybrid. As with all hybrids, take care not to cut through high-or medium-voltage cables. In the Nissan Altima Hybrid, the high-voltage cables run underneath the vehicle roughly in the center of the passenger’s side, not an area typically considered a cutting point. The orange high-voltage cables are not visible on the vehicle’s underside since they are encased in a black plastic track (photo 10).
The basic guidelines for the Nissan Altima Hybrid closely mirror many of the other full-hybrid models that are currently on the road. Prior to extrication operations, always be on the lookout for indicators of a hybrid or other types of alternative-fueled vehicles. This particular model is only sold in California, New England, and the New York/New Jersey regions, so emergency responders in these regions must be on the lookout for it.
If you have been involved in an incident involving hybrid or alternative-fuel vehicles, contact me at Jason@etsrescue.com. Case studies involving specific incidents will help further educate firefighters on the proper methodology for dealing with hybrids and other alternative-fueled vehicles.
Jason Emery has been with the Waterbury (CT) Fire Department for 14 years and is assigned to the rescue/hazmat company. He is an 18-year veteran of the fire service, is a certified fire instructor, and has a bachelor’s degree in fire science from the University of New Haven. He has taught extensively on the subject of hybrid vehicles and is an FDIC lecturer. He is the founder of Emergency Training Solutions, LLC and the lead PowerPoint® designer for the soon to be released Fire Engineering Handbook for Firefighter I & II.
Subjects: Hybrid vehicle hazards and extrication.
