P1C80 on Toyota: How to Diagnose & Fix
Hybrid/EV Battery Voltage System Isolation (Rear Motor Area) Internal Electronic Failure
1 Toyota model · 1 documented issue
P1C80 on Toyota by model: symptoms, diagnosis and fix
Toyota Customer Support Program 22TE09 covers certain 2019-2022 RAV4 Hybrid AWD and 2021-2022 RAV4 Prime vehicles produced within the program's listed periods. Excessive corrosion at the connector between the HV floor-under wire harness and rear traction-motor cable may cause AM-radio static during specified drive selections, P0AA649 and/or P1C8049 with warning messages, or a vehicle that will not start. Toyota does not describe a blanket complete shutdown while driving, loss of AWD, P0AA6/P0A7F/P0AC4 condition or universal cable part number.
Common Symptoms
- AM-radio static that begins when Drive or Reverse is selected and stops in Park
- Hybrid-system warning message or MIL with P0AA649 and/or P1C8049
- Vehicle may not start after warning indicators appear
How to Fix
Check the complete VIN with an authorized Toyota dealer and have the connector inspected under CSP 22TE09. If Toyota's condition and inspection criteria are met, the dealer repairs or replaces the affected floor-under harness and replaces the rear traction-motor cable only when the inspection standard requires it. Program coverage is eight years from first use or 100,000 miles, whichever comes first, and applies only to dealer work under the program terms. Warning messages or a no-start require prompt diagnosis; do not touch or clean a high-voltage connector. Do not order from the removed search links because the floor harness is model-year- and plant-specific.
Owner tips & cautions
- TipBring the complete VIN plus any warning-message photo or scan report; CSP eligibility and the repair path depend on production data, symptoms, DTCs and Toyota's connector inspection.
- WarningThis is a high-voltage circuit. Do not touch, disconnect, probe or clean the underbody connector; use a qualified Toyota hybrid technician.
Sources for this issue (2)
P1C80 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P1C80 mean on a Toyota?
P1C80 stands for "Hybrid/EV Battery Voltage System Isolation (Rear Motor Area) Internal Electronic Failure." The hybrid vehicle control ECU continuously monitors electrical isolation (insulation resistance) between the high-voltage circuit and vehicle chassis ground. P1C80 (stored as P1C8049) sets when the monitored isolation fault is localized to the rear motor area — the Motor Generator Rear (MGR) high-voltage circuit and the HV floor-under wire harness feeding it. Toyota T-SB-0026-22 states the condition is caused by corrosion, dirt, or debris at connector Y6 at the Motor Generator Rear, which degrades insulation between the HV cable and ground. On Toyota it is documented across 1 model: RAV4.
What are the most common causes of P1C80?
The most common causes of P1C80 are: Corrosion inside HV connector Y6 at the Motor Generator Rear (MGR), from road salt/water intrusion, Dirt and debris inside the MGR high-voltage connector, Damaged or degraded HV floor-under wire harness insulation along the underbody routing, Improperly torqued high-voltage bolts or misrouted/unsecured HV cables after prior service. The specific cause varies by vehicle.
How much does it cost to fix P1C80 on a Toyota?
Repair costs vary widely with the root cause and Toyota model; each issue on this page carries its own estimate where one is published.
Looking for P1C80 on a different make?
View P1C80 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.