All Posts

CUSTOMER CONCERN Cabin heater blows cold unless the gasoline engine is running. CAUSE The front electric auxiliary heater coolant pump would not operate when commanded. CORRECTION Remove and replace the auxiliary heater coolant pump and verify cabin heat in electric mode.

CUSTOMER CONCERN StabiliTrak warning is on with Electronic Brake Control Module DTC C0287. CAUSE Confirmed failed B119 multi-axis acceleration sensor after power, ground, and chassis expansion bus checks. CORRECTION Remove and replace the B119 multi-axis acceleration sensor, perform the vehicle yaw sensor learn, clear DTC C0287, and verify stability-control operation.

CUSTOMER CONCERN Air conditioning is inoperative with fault 21F111. CAUSE Confirmed failed rear refrigerant shutoff valve. CORRECTION Remove and replace the rear refrigerant shutoff valve, clear fault 21F111, and verify A/C operation.

CUSTOMER CONCERN After climate-control-head replacement, A/C faults report no basic setting, compressor first run-in not completed, and control module not coded. CAUSE The replacement Automatic Temperature Control head had not been coded to the vehicle and the electric A/C compressor first-run-in routine had not been completed. CORRECTION Code the Automatic Temperature Control head using ODIS Software Version Management, perform basic settings and the compressor first-run-in

CUSTOMER CONCERN ABS warning is on with C1252, C1253, and C1256; after replacement of a melted ABS motor relay, C1256 continues to report low accumulator pressure. CAUSE The ABS actuator pump could not build and maintain normal accumulator pressure after relay power was restored, confirming an internal actuator failure. CORRECTION Remove and replace the ABS actuator assembly, bleed the brake system, clear DTCs, and verify accumulator pressure and brake-assist operation.

CUSTOMER CONCERN Intermittent no-start condition with Check Hybrid System warning and generator-control DTC P0A1A-151. CAUSE Substitution with a known-good inverter/converter assembly eliminated the fault, confirming an internal inverter/converter failure. CORRECTION Remove and replace the inverter/converter assembly, clear DTC P0A1A-151, and program the MG ECU and power-management ECU as specified by campaign E0E before verifying ready-mode operation.

CUSTOMER CONCERN Vehicle will not enter ready mode after an oil change and repeated attempts to reset the maintenance reminder; the combination meter illuminates but the brake warning remains on. CAUSE The 12-volt battery discharged below the level needed to power the hybrid control system during the extended reminder-reset attempts. CORRECTION Remove and replace the failed 12-volt battery and verify the Prius enters ready mode and the maintenance reminder resets normally.

CUSTOMER CONCERN Check Hybrid System warning is on with P0A80, P3000, C1259, and C1310. CAUSE Confirmed failed high-voltage hybrid battery pack. CORRECTION Remove and replace the high-voltage hybrid battery pack, clear DTCs, and verify battery block voltages and hybrid-system operation.

CUSTOMER CONCERN Service Hybrid System warning appears with isolation DTC P0AA6; the fault returns shortly after the A/C is switched on and the compressor is unusually loud. CAUSE The high-voltage isolation fault stopped returning when the electric A/C compressor was disconnected, confirming an internal compressor insulation leak. CORRECTION Remove and replace the electric A/C compressor, clear DTC P0AA6, and verify A/C and hybrid-system operation without an isolation fault.

CUSTOMER CONCERN Smart-key touch unlock does not operate and the vehicle will not start normally with the key present. CAUSE The smart-key system cancel function had been switched on, disabling passive-entry and normal smart-key starting. CORRECTION Enable the smart-key system through the cancel-function setting, perform the scan-tool smart-key location test, and verify passive entry and ready-mode operation.