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Home >> Toyota >> 2012 >> Prius Four >> Repair and Diagnosis (Single Page) >> Hybrid/Electric Powertrain >> Testing and Diagnosis >> Hybrid Control System (Except Plug-In) (Diagnostics - Introduction) >> Hybrid Control System >> Problem Symptoms Table >> Problem Symptoms Table
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Problem Symptoms Table

HYBRID VEHICLE CONTROL SYSTEM

Symptom Suspected Area See
Cannot enter EV mode CAN communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
EV drive mode switch (integration control and panel sub-assembly) -
Pattern select switch EV mode circuit Refer to Pattern Select Switch EV Mode Circuit
EV mode indicator light does not illuminate Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
EV drive mode switch (integration control and panel sub-assembly) -
EV mode indicator light does not turn off Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
EV drive mode switch (integration control and panel sub-assembly) -
Cannot enter POWER mode CAN communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
POWER mode switch (integration control and panel sub-assembly) -
Pattern select switch POWER mode circuit Refer to Pattern Select Switch Power Mode Circuit
POWER mode indicator light does not illuminate Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
POWER mode switch (integration control and panel sub-assembly) -
POWER mode indicator light does not turn off Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
POWER mode switch (integration control and panel sub-assembly) -
Pattern select switch POWER mode circuit Refer to Pattern Select Switch Power Mode Circuit
Cannot enter ECO mode CAN communication system Refer to HOW TO PROCEED WITH TROUBLESHOOTING
Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECO mode switch (integration control and panel sub-assembly) -
Pattern select switch ECO mode circuit Refer to Pattern Select Switch Eco Mode Circuit
ECO mode indicator light does not illuminate Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECO mode switch (integration control and panel sub-assembly) -
ECO mode indicator light does not turn off Combination meter Refer to HOW TO PROCEED WITH TROUBLESHOOTING
ECO mode switch (integration control and panel sub-assembly) -
Pattern select switch ECO mode circuit Refer to Pattern Select Switch Eco Mode Circuit
Hesitation and/or poor acceleration Brake override system Refer to Brake Override System
Loud rattle from hybrid vehicle transaxle Loud Rattle from Hybrid Vehicle Transmission Refer to Loud Rattle from Hybrid Vehicle Transmission
Transmission input damper Refer to COMPONENTS
Hybrid vehicle transaxle assembly Refer to COMPONENTS