The battery in the Honda Insight is easily accessible to service technicians and emergency responders.

Before attempting to rescue occupants from a damaged Honda Insight hybrid vehicle, it is also important to reduce the potential for high-voltage current to flow into the cables from the motor or high-voltage battery. As stated previously, the best method is to turn the ignition switch off. This simple action:

• Turns off the engine and the motor, which prevents electric current from flowing into the cables from the motor or high-voltage battery, and,

• Turns off power to the airbags and the seatbelt pre-tensioners.

After turning off the ignition switch, it is recommended that emergency responders remove the key so the car cannot be inadvertently restarted. To let everyone at the crash scene see that the key is removed, place it on top of the dash, directly in front of the steering column. In this location, it can be viewed from every side of the vehicle.

Disconnect 12-Volt Battery

At this point, the high-voltage system of the Honda Insight or Toyota Prius has been isolated. This improves responder safety in and around the vehicle. We must now, however, work to shut down the 12-volt electrical system on the hybrid just as we typically do on any conventional vehicle.

Locate the 12-volt battery. The battery on the Prius is located inside the driver’s rear wheelwell within the trunk. It is vented through a tube down through the floorpan. On the Insight, the 12-volt battery is under the hood. Disconnecting the battery cable disables the high-voltage battery controller, which prevents electric current from flowing into the orange cables from the high-voltage battery.

If your department’s battery policy is to disconnect cables, locate the negative battery terminal and unbolt the ground cable. Do the same for the positive cable. If your department’s battery shutdown policy is to cut cables, double cut the negative cable first followed by double cuts to the positive one.

With either technique, both 12-volt battery cables need to be removed or cut to ensure rescuer safety at vehicle rescue or car fire operations.

Do not cut any portion of the orange high-voltage wiring harness. Do not touch any bare or exposed wires of this high-voltage system.

With the ignition key turned off and removed and the 12-volt battery disconnected, the hybrid vehicle is safe to work on for vehicle rescue evolutions. High-voltage electricity still exists, but it is isolated to the battery pack in the trunk.

A second action that can be taken while accessing the Insight 12-volt battery is to remove the main fuse. The advantage of pulling the main fuse is that it is an alternate method to turn off the engine and electric motor. With the motor shut off, no high-voltage electric current will flow into the cables from the motor. Removing the main fuse also cuts power to the Insight’s airbags and the two seatbelt pre-tensioners.

Disconnect High-Voltage Battery Pack

The least desirable method of shutting down the hybrid vehicle is to shut down the high-voltage battery directly. This is accomplished by service technicians when these vehicles are being repaired at a dealership. Although emergency scene operations will not require working directly on the high-voltage battery pack, it is included here so responders can become aware of what service technicians are trained to accomplish.

Extra insulation inside various portions of the Toyota Prius body reduces the air conditioner’s load and cuts noise. These insulating materials include foam rubber and Styrofoam. The foam or rubber can be encountered during any roof pillar cutting action, but should not hinder extrication operations.

Repair work on the Toyota Prius includes the service technician removing an orange service plug from the relay unit at the left (driver’s) side of the high-voltage battery. There is a small opening in the trunk carpeting material that must be moved to expose the orange service plug. With the service plug exposed, the technician moves the orange handle down to the horizontal position. The ring on the service plug can then be pulled completely out of the unit.

Because there is a 273.6-volt high-voltage battery in the Prius trunk, Toyota service technicians are technically working near an energized electrical source when they perform work on the vehicle. Toyota advises in its service manual that the use of special certified electrical rubber lineman’s gloves be used when pulling this plug.

On the Honda Insight, service technicians must turn off the battery module switch located below the small cover in the middle of the rear cargo area floor. Then technicians are advised to replace the lock to secure the switch. This is the one area of special notice.

Special Considerations

Are there any special or unique extrication challenges presented by these hybrid vehicles?

There are several additional considerations worthy of mention related to vehicle rescue and extrication on these two hybrid vehicles. These include:

1. Toyota Prius insulation. There is extra insulation inside various portions of the Prius body to reduce the air conditioner’s load and for noise reduction. These insulating materials include foam rubber and Styrofoam. The foam or rubber can be encountered during any roof pillar cutting action, but should not hinder any extrication operations.

2. Vented C-pillar. All the sophisticated electronics onboard the Prius, including the battery pack, generate heat. Borrowing a page from state-of-the-art electronic devices, Prius has a strategically placed vent to help dissipate the heat. Plastic ducting that leads to this vent runs inside the driver’s side C-pillar. Rescue crews will encounter black plastic material when cutting through that C-pillar.

The major advantage of this C-pillar vent for responders is as an aid in identifying the vehicle as a Prius. If as you approach a crashed vehicle you see the hood “badge” with the Toyota logo, you know the car is a Toyota, but it could be a conventional Toyota vehicle. If, however, you move to the driver’s side and see a vented C-pillar, you know it is not just any Toyota, but that in fact it is a Prius. By moving to the rear trunk and visually examining the rear lip you can confirm your suspicions. The logos “Toyota Hybrid” on one side and “Prius” on the other will verify that you are at your first incident involving a Toyota hybrid vehicle.

3. Honda Insight hatchback opening. The Insight rear hatch differs from many Honda models because there is no mechanical linkage between the hatch release on the outside of the vehicle and the actual latch. The exterior latch release is actually a switch that operates a hatch opener relay. A hatch release motor is operated by the relay.

QUICK REFERENCE GUIDE Hybrid Vehicle Emergency Procedures • Hybrid vehicle identification. • Vehicle stabilization. • Access to passenger compartment. • Turn key OFF and remove from ignition. • Check that green light goes out. • Disconnect 12-volt battery.

If the 12-volt battery is discharged or disconnected, the hatch must be opened manually. This can be accomplished by turning the key release located in the right rear taillight lamp all the way to the right while lifting the hatch.

Opening the hatchback may be necessary during extrication. With the hatch open, roof removal can be accomplished without cutting into the pressurized hatchback struts. If the hatchback on the Insight cannot be opened, the roof can still be removed. The rear window glass should be broken first. A forcible entry tool can then be used to pry one end of the hydraulic hatchback lifters off its’ mounting. This allows rear roof pillar cutting to be accomplished without interference from the lifter strut.

If EMS personnel decide to do a rapid extrication, one potential technique is to open the Insight’s hatchback, recline the back of the front seat and extricate the patient onto a longboard out the hatchback opening.

4. Head-on collision. With either hybrid vehicle, there will be a need to access the area under the hood. If the hybrid vehicle has sustained substantial frontal impact, the crumple zone can make hood opening a chore. Try the normal interior hood release mechanism regardless of physical front end damage.

Responders must have multiple forcible entry plans, however, for accessing this engine compartment area, including cutting the hood hinges and pivoting the hood forward on its front latch. This technique positions the rescuer at the side of the vehicle which is safer than standing directly in front. As the rescuer works with a forcible entry bar to pry the hood up at the hinge, the fender and firewall area offer a more stable base to work from.

With the hood bent up enough to expose the hood hinge, the hinge can be cut completely through. With both hinges cut, the hood is then lifted forward, now hinging on the forward latch. This is a relatively quick and efficient method to access the engine compartment of any modern-day vehicle with a jammed hood latch.

5. T-bone collision. A broadside collision that impacts the side of the hybrid vehicle will raise concern about the integrity of the high-voltage battery. If the impact is severe near the rear wheel and the car deforms enough, there could be physical damage to the high-voltage battery pack in the trunk. Be alert to this possibility during your operations.

A T-bone collision also presents the challenge of a potential jammed door. On the Insight, jammed door procedures will be taking place on a lightweight aluminum vehicle with aluminum and plastic body panels. These will react differently during forcible entry than a sheetmetal panel. The spreader may slip as the plastic bends or breaks into pieces. It may be to your advantage to pry or break the plastic panels off completely, exposing the remaining structure of the door. Cutting or delicate spreading can then be directed to whatever is not allowing the door to open.

6. Rear-end collision. A hard-impact rear-end collision to the Toyota Prius hybrid has the potential to physically damage the 12-volt battery. It is within the rear crumple zone. Use caution to not contact a broken and leaking 12 volt battery during operations to open the trunk.

A rear-end collision also has the potential of instantly destroying all hybrid vehicle logos on the Honda Insight and the largest hybrid logos on the Toyota Prius. Be especially alert to this rear area of the vehicle when working to determine the make and model of the vehicle.

If the rear crumple zone is crushed or not accessible, you will have to determine that the vehicle you are working on is or is not a hybrid by checking other indicators. Interior layout that includes the “Ready” or the “Auto Idle Stop” light in the instrument cluster, a vented C-pillar or orange wiring visible when you open the hood all serve as telltale signs of a hybrid vehicle.

7. Rollover collision. If either of the hybrid vehicles rolls over during a crash and ends up on its roof, the vehicle will rest with the front end and hood contacting the ground and the trunk or hatchback elevated. This vehicle position will make hood access very difficult.

A rollover Toyota Prius crash where the vehicle winds up on its roof will still allow for vehicle stabilization, ignition key shutdown and trunk access to the 12-volt battery. Other than the upside-down position, the car can be worked on without any unusual problems.

With the Honda Insight in this rollover position, however, things are different. Upside down, the Insight’s hood will be jammed into the ground. This means that access to shutdown the 12-volt battery will not be possible. With the Insight upside down, you will also not have access to the main fuse.

Disconnecting the battery is one method of shutting down the high-voltage electrical system. Pulling the main fuse, which is just to the driver’s side of this battery, accomplishes the same thing.

With both the battery and the main fuse intact, responders must concentrate on vehicle stabilization and access the interior. Access to the steering column area allows access for turning the Insight’s ignition key to the “Off” position. This action will shut down the 144-volt high-voltage system, but leave the 12-volt functional. Extra caution will have to be taken with a Honda Insight in this condition. Jammed doors or any cutting action will be taking place on a vehicle with a fully functional 12-volt system. Be cautious.

8. Vehicle submersion. If the hybrid vehicle is fully or partially submerged in water, do not touch any of the high-voltage components or orange cables because of the danger of electrocution. It is safe to be around the hybrids in water, and all typical rescue and extrication tasks can be performed on the vehicle.

Additional Resources

There are several additional online resources that will benefit an agency in preparing for hybrid vehicle emergency response.

American Honda Motors has produced a booklet, Honda Insight Emergency Response Guide, May 2001. It is available by contacting a local Honda dealer.

Toyota Motors offers a 26-page booklet, Prius Emergency Responder Guide. The item number is TMS M/N 00400-OTH02-0U. The booklet will be available in the fall of 2001. A copy can be obtained by contacting a local Toyota dealer.