What it means
The BMS detects a circuit low 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 battery management system (BMS) reads voltage from cell groups through individual sense channels; channel T is one of those measurement paths. This code sets when the channel T signal is below the BMS's expected range, so the pack's reading for that group cannot be trusted.
Common causes
Most likely first.
- Sense wire shorted to ground
- Open in sense wire
- Connector pins corroded - high contact resistance
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
- Use a scan tool to save freeze-frame data and compare channel T's reported voltage with nearby cell-group readings, since a low or implausible reading helps confirm the affected path.
- With the vehicle powered down according to the manufacturer's high-voltage safety procedure, inspect channel T's accessible connector and sense-wire routing for damage, corrosion, or signs of a ground short.
- Check that channel T's connector pins are clean, seated, and gripping properly; corrosion or poor contact can pull the signal low.
- Have a qualified hybrid technician test channel T's wiring for continuity and shorts to ground using the manufacturer's procedure, because opening the battery pack can expose hazardous voltage.
- If the wiring and connections pass, compare the channel T input at the battery monitoring module with the manufacturer's specification to determine whether the fault is in the circuit or module.
Common fixes
- Reseat the channel T connector if it is loose.
- Clean or repair corroded channel T connector pins using the approved service method.
- Repair or replace channel T sense wiring that is open, damaged, or shorted to ground.
- Replace or repair the battery monitoring module only if circuit testing confirms an internal fault.
Can I keep driving?
Avoid hard acceleration and long trips if the vehicle has reduced power or enters limp mode; charging may also be limited or unavailable. Arrange prompt hybrid-system diagnosis, and stop driving if the vehicle displays a high-voltage or battery safety warning.
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.