damage the battery pack elements and short them
together by penetrating the battery cell isolators. The
battery pack electrolyte is an alkaline gel that surrounds
the battery plates. This gel will not leak out of the battery
even if the case is broken.
To begin battery pack removal, remove the interior
trim or carpet over the battery, Figure 38-28. Unfasten
the metal cover and any ductwork that prevents battery
pack removal. This will expose the battery pack, power
relays, and other units.
While wearing insulated rubber gloves, remove the
large nuts or fasteners that secure the high-voltage power
cables to the battery pack. To prevent a high-voltage
short, wrap electrical tape around the metal terminals on
the ends of the orange power cables. You do not want
them to accidentally contact anything and conduct high-
voltage electricity.
To remove a battery pack, unbolt it from the vehicle
as required. Then use an engine crane or have someone
help you lift the battery out of the vehicle. The battery
pack should be handled carefully since it contains a
tremendous amount of stored electrical energy and can
be very heavy. A hybrid battery pack can weigh over
200 pounds (90 kg). Make sure your helper is wearing
eye protection and thick rubber insulated gloves.
Place the battery pack on a wooden pallet for ship-
ment to an authorized recycler. Cover the battery pack
with a box or place it in a shipping container. Place
warning tape or high-voltage warning labels on the out-
side of the box or shipping container to warn others of the
high-voltage danger inside.
Checking HV Battery Relays and
Contactors
If the trouble codes and symptoms indicate that the
battery is okay but battery power is not reaching the
power control module, check the operation of the battery
relays and contactors. The contactors turn such a high
electrical load on and off that their lugs can become
burned and pitted. If burned enough, the lugs will
develop high resistance and will not be able to carry
enough current to the power control module and motor-
generator. Refer to factory service information for relay
and contactor test points.
Chapter 38 Hybrid Drive System Operation and Repair 715
Figure 38-27. Hybrid battery packs are normally located in
trunk area or under the rear seat cushion. Remove the rear seat
or trim panels to gain access to the battery pack.
Rear
seat
HV battery
module
Seat rails
Figure 38-28. Remove the metal cover over the battery pack.
This will expose the battery modules, battery ECU, cooling
fans, and other units that affect battery performance. (Toyota)
Upper
cover
Cooling
fan
HV battery
modules
Service
hole cover
Junction
block