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Home >> Infiniti >> 2017 >> QX80 Base, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (4 Of4) >> DTC/Circuit Diagnosis >> DTC P26AB: Multi-Way Control Valve >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

NOTE:

If DTC P26AB is displayed with DTC P0300, P0301, P0302, P0303 or P0304, first perform the trouble diagnosis for P0300, P0301, P0302, P0303, P0304. Refer to DTC INDEX .

Engine coolant temperature has not risen enough to open the multi-way control valve even though the engine has run long enough.

This is due to a leak in the seal or the multi-way control valve being stuck open.

DTC No. Trouble diagnosis name
(Trouble diagnosis content)
DTC detecting condition Possible cause
P26AB ENGINE COOLANT B/V POSI SEN
(Engine coolant bypass valve "A" stuck/open)
The engine coolant temperature does not reach to specified temperature even though the engine has run long enough.
  • Multi-way control valve
  • Leakage from multi-way control valve
  • Engine coolant temperature sensor 1