Diagnostic article Generic OBD-II
P0A88: Low power-module current-sensor signal is not low charging current
P0A88 checks an electrically low current-sensor signal in the GM BAS hybrid power module.
Read before applying this article
Documented application
2009 General Motors diagnostic parameter file 09OBDG08 Engine Diagnostics.pdf. Section-specific modules and calibrations; no per-code model or engine applicability established.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P0A88 is the low-circuit check for the auxiliary power-module current sensor in GM's BAS hybrid summary. Its published criterion is sensor voltage below 0.5 volts while the module is awake. The listed detection interval is one millisecond.
The code concerns the sensor signal
A low electrical signal is not the same as proving that the module delivered too little charging current. The controller is checking whether the sensor output remains within its valid electrical range. Interpreting the reported amperage requires first establishing that the sensor signal is credible.
The same page gives P0A87 a separate current-limit performance comparison and P0A89 the opposite electrical direction. Those distinctions matter when deciding whether the problem is signal range or an in-range reading that disagrees with the operating mode.
Preserve the originating module evidence
Record the sensor-related fault and any relevant power-module status before clearing memory. A normal low-load current display after the event cannot independently establish that the circuit stayed valid when P0A88 set.
The summary supplies no universal connector pins, sensor location or replacement decision. Use the exact hybrid service procedure and appropriate professional test equipment; do not improvise high-current loading or power-electronics probing. Verification should show a credible sensor signal and completed circuit monitoring. An erased code or a battery that charges on one occasion does not establish that the electrical low condition has been corrected.
Source and applicability
2009 General Motors diagnostic parameter file 09OBDG08 Engine Diagnostics.pdf. Section-specific modules and calibrations; no per-code model or engine applicability established. This explanation describes the documented monitor, not a universal repair procedure.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
14 Volt Power Module Current Sensor A Circuit Low
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT