2020 TOYOTA PRIUS C ECU

4788-2. Steps to take in an emergency
PRIUS c_U
NOTICE
■To prevent damage to the vehicle when towing using a wheel-lift type
truck
● Vehicles without a smart key system: Do not tow the vehicle fro m the rear
when the power switch is in the “LOCK” position or the key is r emoved.
The steering lock mechanism is not strong enough to hold the front wheels
straight.
● Vehicles with a smart key system: Do not tow the vehicle from the rear
when the power switch off. The steering lock mechanism is not s trong
enough to hold the front wheels straight.
● When raising the vehicle, ensure adequate ground clearance for towing at
the opposite end of the raised vehicle. Without adequate clearance, the
vehicle could be damaged while being towed.
■ To prevent damage to the vehicle when towing with a sling-type truck
Do not tow with a sling-type truck, either from the front or re ar.
■ To prevent damage to the vehic le during emergency towing
Do not secure cables or chains to the suspension components.

4848-2. Steps to take in an emergency
PRIUS c_U
■SRS warning light
This warning light system monitors the airbag sensor assembly, front impact
sensors, side impact sensors (front door), side impact sensors (front), side
impact sensors (rear), driver’s seat belt buckle switch, front passenger occu-
pant classification system, “AIR BAG ON” indicator light, “AIR BAG OFF” indi-
cator light, front passenger’s seat belt buckle switch, seat be lt pretensioners
(front), airbags, interconnecting wiring and power sources. ( P. 41)
■ Front passenger detection senso r, passenger seat belt reminder and
warning buzzer
● If luggage is placed on the front passenger seat, the front pas senger detec-
tion sensor may cause the warning light to flash and the warnin g buzzer to
sound even if a passenger is not sitting in the seat.
● If a cushion is placed on the seat, the sensor may not detect a passenger,
and the warning light may not operate properly.
■ Electric power steering system wa rning light (warning buzzer)
When the 12-volt battery charge becomes insufficient or the vol tage tempo-
rarily drops, the electric power steering system warning light may come on
and the warning buzzer may sound.
■ If the malfunction indicator lamp comes on while driving
First check the following:
●Is the fuel tank empty?
If it is, fill the fuel tank immediately.
● Is the fuel tank cap loose?
If it is, tighten it securely.
The light will go off after several driving trips.
If the light does not go off even after several trips, contact your Toyota dealer
as soon as possible.
■
When the tire pressure warning light comes on
Check the tire inflation pressure and adjust to the appropriate level. Push-
ing the tire pressur e warning reset switch will not turn off the tire pressure
warning light.
■The tire pressure warning light may come on due to natural caus es
The tire pressure warning light may come on due to natural caus es such
as natural air leaks and tire inflation pressure changes caused by tem-
perature. In this case, adjusting the tire inflation pressure w ill turn off the
warning light (afte r a few minutes).
■When a tire is replace d with a spare tire
The compact spare tire is not equipped with a tire pressure war ning valve
and transmitter. If a tire goes flat, the tire pressure warning light will not
turn off even though the flat tire has been replaced with the s pare tire.
Replace the spare tire with the repaired tire and adjust the ti re inflation
pressure. The tire pressure war ning light will go off after a few minutes.

5028-2. Steps to take in an emergency
PRIUS c_U

Contin-uous
(5 sec-
onds)
An attempt was made to lock
the doors using the smart key
system while the electronic key
was still inside the vehicle.
 Retrieve the electronic key
from the vehicle and lock
the doors again.
Once
Contin-
uous
(5 sec- onds)
An attempt was made to lock
either front door by opening a
door and putting the inside door
lock button into the lock posi-
tion, and then closing the door
while pulling on the outside
door handle with the electronic
key still inside the vehicle.
 Retrieve the electronic key
from the vehicle and lock
the doors again.
Once
• The electronic key could not
be detected when the power
switch was pressed after the
doors were unlocked with the
mechanical key.
• The electronic key could not
be detected two consecutive
times when the power switch
was pressed.
 Touch the electronic key to
the power switch while
depressing the brake
pedal.
Once
An attempt was made to start
the hybrid system with the shift
lever in a position other than P.
Shift the shift lever to P
and start the hybrid sys-
tem.
Interior
buzzerExterior buzzerWarning messageDetails/Actions
(Flashes)
(Flashes)
(Flashes)
(Flashes)

5098-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U
Remove the luggage floor
cover by lifting up the points
indicated by the arrows.
Remove the spare wheel cush-
ions, then loosen the center
fastener that secures the spare
tire.
Taking out the compact spare tire
1
2
WARNING
■When storing the compact spare tire
Be careful not to catch fingers or other body parts between the compact
spare tire and the body of the vehicle.

5168-2. Steps to take in an emergency
PRIUS c_U
WARNING
■When using the compact spare tire
●Remember that the compact spare tire provided is specifically
designed for use with your vehicle. Do not use your compact spare tire
on another vehicle.
●Do not use more than one compact spare tire simultaneously.
●Replace the compact spare tire with a standard tire as soon as possi-
ble.
●Avoid sudden acceleration, abrupt steering, sudden braking and shift-
ing operations that cause sudden engine braking.
■When the compact spa re tire is attached
The vehicle speed may not be co rrectly detected, and the following sys-
tems may not operate correctly:
■Speed limit when using the compact spare tire
Do not drive at speeds in excess of 50 mph (80 km/h) when a com pact
spare tire is installed on the vehicle.
The compact spare tire is not designed for driving at high spee ds. Fail-
ure to observe this precaution ma y lead to an accident causing death or
serious injury.
■After using the tools and jack
Before driving, make sure all t he tools and jack are securely i n place in
their storage locatio n to reduce the possibility of personal in jury during a
collision or su dden braking.
• ABS & Brake assist
• VSC
•TRAC
• Cruise control (if equipped)
• PCS (Pre-collision system) • LDA (Lane Departure Alert)
• Automatic High Beam
• EPS
• Rear view monitor system
• Navigation system (if equipped)

5258-2. Steps to take in an emergency
8
When trouble arises
PRIUS c_U
■Starting the hybrid system when the 12-volt battery is discharged
The hybrid system cannot be started by push-starting.
■ To prevent 12-volt battery discharge
●Turn off the headlights and the audio system while the hybrid s ystem is off.
● Turn off any unnecessary electrical components when the vehicle is running
at a low speed for an extended period, such as in heavy traffic .
■ Precautions when the 12-volt batte ry is discharged (vehicles with a
smart key system)
● In some cases, it may not be possible to unlock the doors using the smart
key system immediately after the 12-volt battery has been disco nnected and
reconnected. Use the wireless remote control or the mechanical key to lock
or unlock the doors.
● The hybrid system may not start on the first attempt after the 12-volt battery
has recharged but will start normally after the second attempt. This is not a
malfunction.
● The power switch mode is memorized by the vehicle. When the 12- volt bat-
tery is reconnected, the system will return to the mode it was in before the
12-volt battery was discharged. Before disconnecting the 12-volt battery,
turn the power switch off.
If the power switch was in ACCESSORY or ON mode before the 12-volt bat-
tery was discharged, the audio system and/or air conditioning system may
operate when the 12-volt battery is reconnected.
■ When the 12-volt battery is removed or discharged
● Information stored in the ECU is cleared. When the 12-volt batt ery is
depleted, have the vehicle inspected at your Toyota dealer.
● Some systems may require initialization. ( P. 565)
■ When removing the 12-vo lt battery terminals
When the 12-volt battery terminals are removed, the information stored in the
ECU is cleared. Before removing the 12-volt battery terminals, contact your
Toyota dealer.
■ Charging the 12-volt battery
The electricity stored in the 12-volt battery will discharge gr adually even when
the vehicle is not in use, due to natural discharge and the dra ining effects of
certain electrical appliances. If the vehicle is left for a lon g time, the 12-volt
battery may discharge, and the hybrid system may be unable to s tart. (The
12-volt battery recharges automatically while the hybrid system is operating.)

5288-2. Steps to take in an emergency
PRIUS c_U
WARNING
■12-volt battery precautions
The 12-volt battery contains poisonous and corrosive acidic ele ctrolyte,
while related parts contain lead and lead compounds. Observe th e following
precautions when handling the 12-volt battery:
● When working with the 12-volt battery, always wear safety glass es and
take care not to allow any battery fluids (acid) to come into c ontact with
skin, clothing or the vehicle body.
● Do not lean over the 12-volt battery.
● In the event that battery fluid comes into contact with the skin or eyes,
immediately wash the affected area with water and seek medical attention.
Place a wet sponge or cloth over the affected area until medica l attention
can be received.
● Always wash your hands after handling the 12-volt battery suppo rt, termi-
nals, and other 12-volt battery-related parts.
● Do not allow children near the 12-volt battery.
■ When replacing the 12-volt battery
After replacing, securely attach the exhaust hose and exhaust h ole plug to
the exhaust hole of the exchanged 12-volt battery. If not properly installed,
gases (hydrogen) may leak into the vehicle interior, and there is a possible
danger of the gas igniting and exploding.
NOTICE
■ When handling jumper cables
When connecting the jumper cables, ensure that they do not beco me entan-
gled in the cooling fan or belt.
■ To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when chargin g the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump
start another vehicle.

5599-1. Specifications
9
Vehicle specifications
PRIUS c_U
*: Table 1  Occupant loading and distribution for vehicle normal load for
various designated seating capacities
Snow tire
A tire that attains a traction index equal to or
greater than 110, compared to the ASTM E-
1136 Standard Reference Test Tire, when
using the snow traction test as described in
ASTM F-1805-00, Standard Test Method for
Single Wheel Driving Traction in a Straight
Line on Snow-and Ice-Covered Surfaces, and
which is marked with an Alpine Symbol ( )
on at least one sidewall
Te s t r i m The rim on which a tire is fitted for testing, and
may be any rim listed as appropriate for use
with that tire
Tread That portion of a tire that comes into contact
with the road
Tread rib A tread section running circumferentially
around a tire
Tread separation Pulling away of the tread from t he tire carcass
Treadwear indicators
(TWI) The projections within the principal grooves
designed to give a visual indication of the
degrees of wear of the tread
Wheel-holdin g fixtureThe fixture used to hold the wheel and tire
assembly securely during testing
Tire related termMeaning
Designated seating
capacity, Number of occupantsVehicle normal load,
Number of occupantsOccupant distribution
in a normally loaded vehicle
2 through 4 2 2 in front
5 through 10 32 in front, 1 in second
seat
11 through 15 52 in front, 1 in second
seat, 1 in third seat, 1
in fourth seat
16 through 20 72 in front, 2 in second
seat, 2 in third seat, 1
in fourth seat