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 battery condition monitor (BCM) module 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 25.4 seconds.

Driving Pattern
1. Reset the BCM module. (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 gauge (BAT) indicates full charge.
3. Turn the ignition switch to LOCK (0).
4. Repeat steps 1-3 five times.
5. Start the engine.
6. Let the engine idle for at least 3 minutes.

- If you have difficulty duplicating the DTC, retest after turning off electrical components such as the audio system and A/C, and try a different gear.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM and the BCM module memory.

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.