Advanced Diagnostics

Advanced Diagnostics - DTC P1446 (74): Battery Module Individual Voltage Input Deviation






General Description
Each channel monitors the voltage of 12 cells. When one cell in a channel is abnormal, the voltage differs by 1.2 V from the other channels. Therefore, if the difference between channels increases to 1.2 V or more, at least one cell is considered to be abnormal, or the voltage detection system is considered to be abnormal. If the difference between the channels is a specified value for a set time, the motor control module (MCM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The voltage difference between channels is 1.2 V or more for at least 26 seconds.

Driving Pattern
1. Reset the MCM. (Disconnect the 12 V battery terminal once and reconnect it.)
2. Start the engine, and hold the engine speed to between 3,500 - 4,000 rpm (in P or N) until the IMA battery level indicator shows a full charge.
3. Turn the ignition switch to LOCK (0).
4. Repeat step 1 through step 3 five times.
5. Start the engine.
6. Let the engine idle for at least 3 minutes.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the MCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.