Toyota 16660-21011
Reserve Tank

The installation process begins by installing 2 claws that fit into the vehicle side before inserting the stud bolt but maintaining tight pressure on the coolant storage tank to stop bracket bending. The coolant heat storage tank bracket should be moved forward while fastening bolts 1 and 2 to their proper torque of 19 Nm (194 kgf-cm, 14 ft-lbf). Then install the 4 bolts and nut. Secure the tank before connecting first the water pump motor and temperature sensor connectors then the 2 hoses. Begin by wiring the cable to the battery negative terminal and afterward install rear No. 3 floor board and its corresponding rear deck floor box and rear No. 2 floor board. The procedure requires adding engine coolant followed by a check for any leaks in the coolant system. Proceed with the installation of front fender liner LH together with front bumper cover and engine under cover RH then engine under cover LH. The radiator support opening cover should go next for installation followed by system initialization which becomes mandatory after the cable is disconnected from the negative (-) battery terminal.

Service of the coolant reservoir system requires first removing three panels: the rear No. 2 floor board, rear deck floor box, and rear No. 3 floor board. Remove the battery cable negative terminal before letting at least 90 seconds pass to avoid Air Bag and seat belt pretensioner activation. Start by removing the radiator support opening cover followed by engine under covers (LH and RH) together with front bumper cover yet retaining part of the front fender liner LH. Drain the engine coolant through the drain cock plug while being cautious since heat from the reservoir has not fully cooled down. Disassembling the coolant reservoir requires removing two hoses followed by disconnecting water pump motor and temperature sensor connectors before removing the nut and four bolts when securing the Coolant Reservoir tightly to avert bracket deformation. When installing the coolant reservoir assembly begin by clamping the two claws and stud bolt onto the vehicle side and fasten with four bolts and a nut before torquing to 19 Nm (194 kgf-cm, 14 ft. lbs.) while ensuring to press the bracket in front of the vehicle during bolt tightening of 1 and 2. The water pump motor and temperature sensor connectors need to be attached before joining both hoses. Replace all parts by reattaching the negative battery terminal connection then reinstalling the rear No. 3 floor board plus rear deck floor box and rear No. 2 floor board. The service completion includes adding engine coolant and leak detection while placing back the front fender liner LH followed by front bumper cover and engine under covers (RH and LH) and radiator support opening cover. After removing the battery perform initialization because several systems need this step before reconnecting the power supply.

Disconnect the cable from the battery negative terminal, waiting at least 90 seconds to prevent airbag and seat belt pretensioner activation.

Disconnect the 2 hoses, the water pump motor, and temperature sensor connectors, then remove the nut and 4 bolts while holding the tank tightly to avoid bending the bracket.

Be cautious, as the tank surface may become hot if there are malfunctions, and avoid touching it to prevent burns.