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492
uuMaintenance Under the Hood uCooling System
Maintenance
Cooling System
Coolant is used to reduce the temperature  of the high voltage battery and inverter 
coolant. When checking the c oolant level, make sure to follow the procedures listed 
below. If the coolant level is below the  MIN mark, have your vehicle inspected by an 
authorized Honda  Clarity Plug-In Hybrid dealer.
1.Check the fluid level in the tank.
2. If the coolant level has dropped below the 
MIN  level, have your vehicle serviced at an 
authorized Honda Clarity Plug-In Hybrid 
dealer.
u Only a properly trained technician can 
refill the coolant an d check the system 
for leaks.
Specified coolant: Honda Long  Life Antifreeze/Coolant Type 2
■Checking the Inverter Coolant Level
1Cooling System
NOTICE
Genuine Honda engine coolan t is a 50/50 mixture of 
antifreeze and water that can withstand freezing at 
temperatures as low as about −31°F (−35°C). If your 
vehicle is consistently subjected to temperatures 
below this, the concentration of antifreeze in the 
coolant should be  increased. Consult an authorized 
Honda Clarity Plug-In Hybrid dealer for details.
Only use the genuine Honda coolant.
Expansion Tank
MAX
MIN
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495
uuMaintenance Under the Hood uRefilling Window Washer Fluid
Maintenance
Refilling Window Washer Fluid
Check the amount of window washer fluid  using the washer fluid level gauge on the 
cap. If the level is low, fill the washer reservoir.
If the washer fluid is low, the washer level 
indicator comes on.
Pour the washer fluid carefully.  Do not overflow the reservoir.1Refilling Window Washer Fluid
NOTICE
Do not use engine antifreeze or a vinegar/water 
solution in the windshield washer reservoir.
Antifreeze can damage y our vehicle’s paint. A 
vinegar/water solution ca n damage the windshield 
washer pump.
Use only commercially avai lable windshield washer 
fluid.
Avoid prolonged use of hard  water to prevent lime 
scale build up.
Level Gauge
Canadian models
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521
Maintenance
Accessories and Modifications
Accessories
When installing accessories, check the following:
• Do not install accessories on the windsh ield. They can obstruct your view and 
delay your reaction to driving conditions.
• Do not install any accessories over areas  marked SRS Airbag, on the sides or backs 
of the front seats, on front or side pillars, or near the side windows. Accessories 
installed in these areas may interfere wi th proper operation of the vehicle’s 
airbags or may be propelled into you or another occupant if the airbags deploy.
• Be sure electronic accessories do not overload  electrical circuits or interfere with 
proper operation of your vehicle.
2 Fuses  P. 555
•Before installing any electronic accessory, have the installer contact an authorized 
Honda Clarity Plug-In Hybrid dealer for assi stance. If possible, have an authorized 
Honda Clarity Plug-In Hybrid dealer inspect the final installation.
1 Accessories and Modifications
Honda Genuine accessor ies are recommended to 
ensure proper operati on on your vehicle.
3WARNING
Improper accessories or modifications can 
affect your vehicle’s handling, stability, and 
performance, and cause a crash in which 
you can be seriously hurt or killed.
Follow all instruction s in this owner’s 
manual regarding accessories and 
modifications.
3WARNING
Use of improperly designed, engineered or 
manufactured high-voltage battery 
assemblies could cause a fire in your 
vehicle.
A vehicle fire could result in a crash or 
injury.
Only use a genuine Honda high-voltage 
battery assembly, or it s equivalent, in your 
vehicle.
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uuIf a Tire Goes Flat uTemporarily Repairing a Flat Tire
532
Handling the Unexpected
• Greater than 25 psi (175 kPa), but less 
than 36 psi (250 kPa):
Turn the air compressor on to inflate the 
tire until the tire pressure reaches 36 psi 
(250 kPa).
2 Inflating an Under-inflated Tire  P. 533
Then drive carefully for 10 more minutes 
or until you reach the nearest service 
station, whichever is sooner. Do not 
exceed 50 mph (80 km/h). If you have not 
reached a service station after 10 minutes, 
stop in a safe place and check the tire 
pressure.
u You should repeat this procedure as 
long as the air pressure is within this 
range.
7. Unplug the kit from the accessory power 
socket.
8. Unscrew the air only  hose from the tire 
valve stem. Reinstall the valve cap.
9. Press the pressure relief button until the 
gauge returns to 0 psi (0 kPa).
10. Repackage and properly stow the kit.
Pressure Relief Button
1Distributing the Sealant in the Tire
3WARNING
Running the engine with the vehicle in an 
enclosed or even partly enclosed area can 
cause a rapid build-up of toxic carbon 
monoxide.
Breathing this colorless, odorless gas can 
cause unconsciousness and even death. 
Only run the engine  to power the air 
compressor with th e vehicle outdoors.
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542
uuJump Starting u
Handling the Unexpected
5.Connect the other end of the second 
jumper cable to the power system 
mounting bolt as shown. Do not connect 
this jumper cable to any other part of the 
vehicle.
6. If your vehicle is connected to another 
vehicle, start the assi sting vehicle’s engine, 
and increase its rpm slightly.
7. Attempt to start your vehicle’s power 
system. If it does not tu rn on, check that the 
jumper cables have good metal-to-metal 
contact.
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uuOverheating uHow to Handle Overheating
546
Handling the Unexpected
■Next thing to do
1.Check that the cooling fan is operating and 
turn the power system off once the  Stop 
Driving When Safe. Engine 
Temperature Too Hot  message 
disappears.
u If the cooling fan is not operating, 
immediately turn the power system off.
2. Once the engine has  cooled down, inspect 
the coolant level an d check the cooling 
system components for leaks.
u If the coolant level in the reserve tank is 
low, add coolant until it reaches the 
MAX  mark.
u If there is no coolan t in the reserve tank, 
check that the radiator is cool. Cover the 
radiator cap with a heavy cloth and open 
the cap. If necessary, add coolant up to 
the base of the filler neck, and put the 
cap back on.
■Last thing to do
Once the engine has cooled sufficiently, turn the power system on.
If the  Stop Driving When Safe. Engine Temperature Too Hot  message does not 
appear, resume driving. If it appears ag ain, contact an authorized Honda Clarity 
Plug-In Hybrid dealer for repairs.
1 The  Stop Driving When Safe.  Engine Temperature Too 
Hot Message Appears on the Multi-Information Display
If the coolant is leaking, contact an authorized Honda 
Clarity Plug-In Hybrid  dealer for repairs.
Use water as an emergency/temporary measure only. 
Have an authorized Honda Clarity Plug- In Hybrid 
dealer flush the system wi th proper antifreeze as 
soon as possible.
3WARNING
Removing the radiator cap while the 
engine is hot can cause the coolant to spray 
out, seriously scalding you.
Always let the engine and radiator cool 
down before removing  the radiator cap.
Reserve Tank
MAX
MIN
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        Page 549 of 591
547
Handling the Unexpected
Indicator, Coming On/Blinking
If the Low Oil Pressure Warning Appears
■Reasons for the Warning to appear
Appears when the engine oil pressure is low.
■What to do as soon as the warning 
appears
1. Immediately park the vehicle on level 
ground in a safe place.
2. If necessary, turn the hazard warning lights 
on.
■What to do after parking the vehicle
1. Stop the engine and let it sit for 
approximately three minutes.
2. Open the hood and ch eck the oil level.
2Oil Check P. 485
3.Start the engine and check the low oil 
pressure warning.
u The warning disappears: Start driving 
again.
u The warning does not disappear within 
10 seconds: Immediately stop the engine 
and contact an authorized Honda Clarity 
Plug-In Hybrid dealer for repairs.
1If the Low Oil Pressure Warning Appears
NOTICE
Running the engine with low oil pressure can cause 
serious mechanical damage almost immediately.
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549
uuIndicator, Coming On/Blinking uIf the Malfunction Indicator Lamp Comes On or Blinks
Handling the Unexpected
If the Malfunction Indica tor Lamp Comes On or 
Blinks
■Reasons for indicator lamp  to come on or blink
• Comes on when there is a problem  with the engine emissions control 
system, or the fuel fill cap is missing, or loose.
• Blinks when engine misfiring is detected.
■What to do when the  indicator lamp comes on
Avoid high speeds and immediately ge t your vehicle inspected at an 
authorized Honda Clarity  Plug-In Hybrid dealer.
■What to do when the indicator lamp blinks
Park the vehicle in a safe place with  no flammable items and wait at least 
10 minutes or more with the power system stopped until it cools.
■The message appears on when:
An evaporative system leak is  detected. This may be caused  by the fuel fill cap being 
loose or not being installed.
■What to do when the message appears:
1. Stop the power system.
2. Check if the fuel fill cap is fully installed.
u If not, loosen the cap, and then retight en it until it clicks at least once.
3. Drive for several days of normal driving.
u The message should go off.
■When the malfunction indicator lamp comes on
The malfunction indicator lamp comes on if  the system continues to detect a leak of 
gasoline vapor. If this happens, follow th e procedures described earlier to check the 
fuel fill cap.
■Tighten Fuel Cap Message
1 If the Malfunction Indicato r Lamp Comes On or Blinks
NOTICE
If you drive with the malf unction indicator lamp on, 
the emissions control system and the engine could be 
damaged.
If the malfunction  indicator lamp blinks again when 
restarting the engine, drive to the nearest an 
authorized Honda Clarity Plug- In Hybrid dealer at 31 
mph (50 km/h) or less. Have your vehicle inspected.
19 CLARITY PHEV-31TRW6100.book  549 ページ  2018年10月25日 木曜日 午後2時29分