Page 403 of 600
403
6 
 6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Engine compartment
GS450h
■12-volt battery 
 P. 412
Engine oil level dipstick 
( P. 406) 
Engine coolant reservoir  
( P. 409) 
Engine oil filler cap ( P. 407) 
Power control unit coolant  
reservoir ( P. 409) 
Fuse box  ( P. 437) 
Washer fluid tank  ( P. 411) 
Electric cooling fans 
Condenser ( P. 411) 
Radiator ( P. 411)
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        Page 404 of 600
4046-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
GS300h
■12-volt battery 
 P. 412
Power control unit coolant  
reservoir ( P. 409) 
Engine oil level dipstick 
( P. 406) 
Engine oil filler cap ( P. 407) 
Engine coolant reservoir  
( P. 409) 
Fuse box  ( P. 437) 
Washer fluid tank  ( P. 411) 
Electric cooling fans 
Condenser ( P. 411) 
Radiator ( P. 411)
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7
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        Page 437 of 600
437
6 
 6-3. Do-it-yourself maintenance
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
Checking and replacing fuses
Turn the power switch off. 
Open the fuse box cover. 
Engine compartment: 
Remove the engine compartment 
cover ( P. 405) and remove all of the 
clips. 
Push the tabs on either side to detach 
the lock and lift the lid off while pulling 
the lock plate.
When installing the lid, check that the lock plate and the tabs on either side are 
connected correctly.
If any of the electrical components do  not operate, a fuse may have blown. If 
this happens, check and repl ace the fuses as necessary.
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        Page 440 of 600
4406-3. Do-it-yourself maintenance
GS450h_300h_OM_OM30F92E_(EE)
Check if the fuse is blown. 
Normal fuse 
Blown fuse
Type A and B: 
Replace the blown fuse with a new fuse of an appropriate amperage rating. The amperage rating can be found on the fuse box lid. 
Type C and D: 
Contact any authorized Lexus retailer or Le xus authorized repairer, or any reliable repairer.
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Type AType B
Type CType D 
     
        
        Page 441 of 600

441 6-3. Do-it-yourself maintenance
6
Maintenance and care
GS450h_300h_OM_OM30F92E_(EE)
■After a fuse is replaced
●If the lights do not turn on even after the fuse has been replaced, a bulb may need replacement. ( P. 442)
●If the replaced fuse blows again, have the vehicle inspected by any authorized Lexus 
retailer or Lexus authorized repa irer, or any reliable repairer.
■If there is an overload in a circuit 
The fuses are designed to blow, protecting the wiring harness from damage.
■When replacing light bulbs
Lexus recommends that you us e genuine Lexus products designed for this vehicle. Because certain bulbs are connected to circuits designed to prevent overload, non-gen- 
uine parts or parts not designed for this vehicle may be unusable.
WARNING
■To prevent system breakdowns and vehicle fire 
Observe the following precautions. Failure to do so may cause damage to the vehicle, and possibly a fire or injury.
●Never use a fuse of a higher amperage rating than that indicated, or use any otherobject in place of a fuse.
●Always use a genuine Lexus fuse or equivalent. 
Never replace a fuse with a wire, even as a temporary fix.
●Do not modify the fuses or fuse boxes.
NOTICE
■Before replacing fuses 
Have the cause of electrical overload determined and repaired by any authorized Lexus retailer or Lexus authorized repairer, or  any reliable repairer as soon as possible. 
     
        
        Page 530 of 600
5307-2. Steps to take in an emergency 
GS450h_300h_OM_OM30F92E_(EE)
If the 12-volt battery is discharged
If you have a set of jumper (or booster) cables and a second vehicle with a 12-volt 
battery, you can jump start your vehicle by following the steps below. 
Confirm that the electronic key is 
being carried.
When connecting the jumper (or 
booster) cables, depending on the situa- tion, the alarm may activate and doorslocked. ( P. 93)
Open the hood (P. 401), remove 
the engine compartment covers 
( P. 405) and open the fuse box 
cover. 
Remove all of the clips. 
Push the tabs on either side to 
detach the lock and lift the lid off 
while pulling the lock plate. 
Open the exclusive jump starting 
terminal cover.
The following procedures may be used to start the hybrid system if the 12-volt
battery is discharged. 
You can also call any authorized Lexus retailer or Lexus authorized repairer, 
or any reliable repairer.
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        Page 588 of 600

588Alphabetical index
GS450h_300h_OM_OM30F92E_(EE)
Fuel ............................................................. 257 
Capacity .................................................549 
Fuel gauge.............................................. 105 
Information ........................................... 559 
Refueling ................................................ 257 
Type ........................................................  549 
Warning light ....................................... 462 
Warning messages...........................466 
Fuel consumption 
Average fuel consumption .............. 113 
Average fuel consumption  
after refueling ...................................... 113 
Current fuel consumption................ 113 
Fuel filler door ........................................ 257 
Refueling ................................................ 257 
When the fuel filler door  
cannot be opened ......................... 259 
Fuses .......................................................... 437 
Gauges ...................................................... 104 
Glove box ................................................ 370 
Glove box light ...................................... 370 
Grille Shutter system 
Warning message.............................466 
Hands-free system  
(for cellular phone)*
Head restraints ....................................... 183
Headlight cleaner...................... 252, 254 
Headlights ............................................... 237 
Adaptive Front-lighting  
System (AFS)................................... 239 
AHS (Adaptive High-beam  
System) ................................................. 241 
Automatic High Beam  
system.................................................. 246 
Follow me home system................ 238 
Headlight leveling warning  
message ............................................. 466 
Light switch............................................ 237 
Replacing light bulbs ....................... 449 
Head-up display....................................... 119 
Heated steering wheel.........................361 
Heaters ..................................................... 346 
Air conditioning system ................. 346 
Heated steering wheel ................... 362 
Outside rear view mirrors ............ 352 
Seat heaters.......................................... 362 
High-voltage components .................. 80 
Hood........................................................... 401 
Open ......................................................... 401 
Warning message ............................ 466
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