What it means
The BMS detects a circuit intermittent/erratic fault on voltage sense channel T of the high-voltage battery. Cell-group voltage measurement is unreliable on this channel.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The BMS uses channel T to read the voltage of a particular cell group in the high-voltage battery. This code sets when that channel's signal changes erratically or intermittently, so the BMS cannot rely on a stable reading and may limit battery use.
Common causes
Most likely first.
- Sense connector not seated
- Noisy ground reference
- Connector with intermittent contact under vibration
Symptoms
- EV/hybrid system warning light on
- Reduced power output or limp mode
- Charging may fail or be slowed
- Reduced electric range
How to diagnose it
- Save freeze-frame data and review channel T's live voltage while stationary, then compare it with adjacent cell-group readings for sudden jumps or dropouts.
- With the vehicle shut down using the manufacturer's high-voltage safety procedure, inspect the channel T connector for incomplete seating, corrosion, or damaged pins.
- Inspect the channel T harness and its ground-reference connections for looseness, chafing, or strain that could make contact change with vibration.
- Have a qualified hybrid technician monitor channel T while checking connector fit and wiring continuity under the manufacturer's approved wiggle-test procedure.
- If the connection and wiring remain stable, test the channel T ground reference and battery monitoring module input against the manufacturer's specification.
Common fixes
- Fully seat and secure the channel T connector.
- Clean or repair channel T connector pins with intermittent or corroded contact.
- Repair loose, damaged, or poorly secured channel T wiring or ground-reference connections.
- Replace the battery monitoring module only if testing confirms its channel T input is unstable.
Can I keep driving?
Avoid demanding acceleration and long journeys if power is reduced, since the BMS may limit output with little notice; charging may also be interrupted. Arrange prompt diagnosis, and stop if a battery safety warning appears.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.