DTC P0B29 (74)
DTC P0B29 (74): HV Battery Pack B Voltage Low
General Description
If one of the following conditions occurs, the battery condition monitor module B detects a malfunction and stores a DTC:
- Malfunction judgment 1
The voltage difference between the maximum cell voltage and the minimum cell voltage exceeds a specified voltage immediately after the vehicle condition is turned to the ON mode.
- Malfunction judgment 2
The voltage difference between the maximum cell voltage and the minimum cell voltage exceeds a specified voltage for a specified duration.
- Malfunction judgment 3
The individual cell voltage falls below a minimum voltage for a set duration.
- Malfunction judgment 4
The SOC variability occurs between the battery modules of the battery pack for a specified duration.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | - |
| DTC Type | One drive cycle, MIL on, POWER SYSTEM indicator on, 12 volt battery charging system indicator off |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Battery pack temperature | 50 deg.F (10 deg.C) | - |
| Battery pack current | -3 A | 12 A |
| Vehicle condition | Vehicle ON mode, or Plug-in charge on, or Plug-in quick charge on | |
Malfunction Threshold
One of the conditions is met:
- Malfunction judgment 1
The voltage difference between the maximum cell voltage and the minimum cell voltage is more than 0.52 V immediately after the vehicle condition is turned to the ON mode.
- Malfunction judgment 2
The voltage difference between the maximum cell voltage and the minimum cell voltage is more than 0.97 V for at least 5 seconds.
- Malfunction judgment 3
The individual cell voltage is 1.5 V or less for at least 10 seconds.
- Malfunction judgment 4
There is a battery module that the chargeable SOC is less than 0 %, and a battery module that the dischargeable SOC is less than 0 %. These conditions continue for at least 5 seconds.
Possible Cause
- Battery pack internal circuit failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, the MIL and the POWER SYSTEM indicator comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the battery condition monitor module B memory.
Conditions for clearing the DTC
The MIL and the POWER SYSTEM indicator are cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL and the POWER SYSTEM indicator, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.