Lexus 2012 RX450h Owner's Manual page 926

5-2. Steps to take in an emergency
Connect the clamp at the other end of the negative cable to a solid,
stationary, unpainted metallic point away from the exclusive jump
starting terminal and any moving parts, as shown in the illustration.
Start the engine of the second vehicle. Increase the engine
STEP 4
speed slightly and maintain that level for approximately 5 min-
utes to recharge the 12-volt battery of your vehicle.
Open and close any of the doors of your vehicle with the
STEP 5
"POWER" switch off.
Maintain the engine speed of the second vehicle and start the
STEP 6
hybrid system of your vehicle by turning the "POWER" switch
to ON mode.
Make sure the "READY" indicator comes on. If the indicator
STEP 7
does not come on, contact your Lexus dealer.
Once the hybrid system has started, remove the jumper cables
STEP 8
in the exact reverse order from which they were connected.
Once the hybrid system starts, have the vehicle inspected at your
Lexus dealer as soon as possible.
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