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Fc System Malfunction Toyota Mirai

KR
The Creator
May 17, 2026
“FC System Malfunction” : r/Mirai
“FC System Malfunction” : r/Mirai www.reddit.com
“FC System Malfunction” : r/Mirai
“FC System Malfunction” : r/Mirai www.reddit.com

The multi-information display shows warnings for system malfunctions and incorrectly performed operations, and messages that indicate a need for maintenance. When a message is displayed, perform the appropriate corrective action for the message. If a warning message is displayed again after the appropriate actions have been performed, contact your Toyota dealer.

FCV System malfunction. 1600 miles only : r/Mirai
FCV System malfunction. 1600 miles only : r/Mirai www.reddit.com

Additionally, if a warning. Welcome to r/Mirai, a sub about the Toyota Hydrogen Electric Mirai. My warning light "FC System Malfunction" turned on on my 2017 Mirai after fueling last night.

Reset Toyota Pre-Collision System Malfunction: Easy Guide 2024
Reset Toyota Pre-Collision System Malfunction: Easy Guide 2024 bryansgarage.com

When I took it to the dealership for diagnostics, they said that the receptacle was damaged and is leaking gas. Some 2016 - 2019 model year Mirai vehicles may exhibit a warning message, "FC malfunction, return vehicle to dealer for service." This message is accompanied by Diagnostic Trouble Code (DTC) P1DEF (450 FC Stack Performance). The Fuel Control Module (FCM) calibration has been revised to address this condition.

FCV Malfunction in 2021 Mirai XLE : r/Mirai
FCV Malfunction in 2021 Mirai XLE : r/Mirai www.reddit.com

The Toyota Mirai relies heavily on the fuel cell stack for power generation, so any malfunction in this system can weaken overall performance. If your Mirai struggles to accelerate, maintain speed, or climb hills as it normally would, a faulty fuel cell system may be the cause. I am an owner of a second hand toyota mirai 2017.

FCV Malfunction in 2021 Mirai XLE : r/Mirai
FCV Malfunction in 2021 Mirai XLE : r/Mirai www.reddit.com

It was doing great until yesterday it won't start and there was a message saying FC System Malfunction Contact your Dealer. Did it happen to anyone here? If so was it covered by th warranty? Some 2016 - 2019 model year Mirai vehicles may exhibit a warning message, "FC malfunction, return vehicle to dealer for service." This message is accompanied by Diagnostic Trouble Code (DTC) P1DEF (450 FC Stack Performance).

“Pre-collision system malfunction” warning in Toyota vehicles - YouTube
“Pre-collision system malfunction” warning in Toyota vehicles - YouTube www.youtube.com

Took car to the dealer this morning with the "FCV Malfunction" message still showing. Turned car off while waiting in the intake line, then turned car back on to move forward, the "FCV Malfunction" message no longer shows. TSB: some 2016? 2019 model year mirai vehicles may exhibit a warning message,?Fc malfunction, return vehicle to dealer for service.? This message is accompanied by diagnostic trouble code (DTC) p1def (450 fc stack performance).