DTC P154A
DTC P154A: Battery Sensor Internal Failure
General Description
The local interconnect network (LIN) line connects the 12 volt battery sensor and the powertrain control module (PCM). The LIN uses a master/slave protocol to send and receive data to the different components on the line. The PCM is the master unit, which controls the engine electrical system, and the 12 volt battery sensor unit is the slave that receives data and provides feedback to the PCM. The 12 volt battery sensor is connected between the 12 volt battery and ground. The 12 volt battery sensor measures the 12 volt battery's current, voltage, and temperature. When the PCM requests this information to operate the engine electrical system efficiently, the 12 volt battery sensor runs a diagnostic program and sends the results to the PCM via the LIN. If the diagnostic results are outside the normal range, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type, OBD Status
| Execution | Continuous |
| Sequence | None |
| Duration | 5 seconds or more |
| DTC Type | One drive cycle, MIL off |
| OBD Status | PASSED/FAILED/NOT COMPLETED (STILL TESTING) |
Enable Conditions
| Condition | |
|---|---|
| Vehicle | ON mode |
| No active DTCs set (prevents monitor from running) | P16E3 |
Malfunction Threshold
Any of the conditions is met for at least 5 seconds:
- Internal current detection circuit open or A/D conversion circuit abnormal
- Internal voltage detection circuit open/short or A/D conversion circuit abnormal
- Internal temperature detection circuit open/short or A/D conversion circuit abnormal
- 12 volt battery internal resistance measuring circuit or power supply system abnormal
- Calibration data abnormal
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- 12 volt battery sensor power supply line open (include fuse fall-outs)
- 12 volt battery sensor internal failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected, a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory. The MIL does not come on.
Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.