Advanced Diagnostics

Advanced Diagnostics - DTC P154A: Battery Sensor Internal Failure (Engine Type: R18Z1, R18A9)

General Description






The local interconnect network (LIN) line connects the battery sensor and the engine control module (ECM)/powertrain control module (PCM). The LIN uses a master/slave protocol to send and receive data to the different components on the line.
The ECM/PCM is the master unit, which controls the engine electrical system, and the battery sensor unit is the slave that receives data and provides feedback to the ECM/PCM.
The battery sensor is connected between the 12 volt battery and ground. The battery sensor measures the 12 volt battery's current, voltage, and temperature. When the ECM/PCM requests this information to operate the engine electrical system efficiently, the battery sensor runs a diagnostic program and sends the results to the ECM/PCM via the LIN. If the diagnostic results are outside the normal range, the ECM/PCM detects a malfunction and stores DTC.

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






Enable Conditions






Malfunction Threshold
Either one 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 or A/D conversion circuit abnormal
- Internal temperature detection circuit open or A/D conversion circuit 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.

- 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 ECM/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 battery.