If the surface is corroded or if the blades are damaged, replace the impeller

Water Pump Impeller Disassembly/Assembly
Water Pump Housing DisassemblyBackups
The ECU takes the following measures to prevent engine damage when the
DFI, ignition, S-KTRC
or immobilizer system parts have troubles.
Note:
(1): D-J Method: When the engine load is light like at idling or low
speed, the ECU determines the
injection quantity by calculating fr ...
KIBS Motor Relay Inspection (Service Code b 35)
Check the KIBS motor relay fuse (25 A) [A] (see Fuse
Inspection in the Electrical System chapter)
If the fuse is good, check the wiring continuity as follows.
Disconnect:
Battery Positive Cable (see Battery Removal in the Electrical
System chapter)
KIBS Hydraulic Unit Lead Connector (see ...
Mud Guard Installation
Installation is the reverse of removal. Note the following.
Run the hose and lead correctly (see Cable, Wire, and
Hose Routing section in the Appendix chapter).
Check the brake line.
Apply a non-permanent locking agent to the threads of
the mud guard mounting bolts [A, B], and tighten them ...