Diagnostic article Generic OBD-II
P0D17: Charging interlock low while its reference is sourced
P0D17 detects insufficient charging-interlock feedback during the documented GM five-volt sourced test state.
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Documented application
15OBDG01 Hybrid Diagnostics, cited controller and monitor only. Historical calibration limits are not universal specifications; per-code vehicle, engine and hardware applicability must be verified.
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.
Low relative to an active source
The GM P0D17 charging high-voltage-interlock monitor asks whether the sensed signal is sufficiently high when the controller intentionally sources its reference. The source state must be “sourced,” identified as 5 volts in the table. A sensed value below 30% of reference meets the low-circuit failure criterion.
This commanded-state requirement separates P0D17 from a general observation that an interlock line happens to be low. During an unsourced phase, a low signal has a different meaning. Reading a voltage without the source state could therefore lead to the wrong diagnosis.
What the timing and companion code reveal
The monitor requires two failed samples out of two, with a 12.5-millisecond sample period, and the 12-volt supply must exceed 10.2 volts. The stated pass time is 25 milliseconds. These short diagnostic intervals describe electronic monitoring; they do not establish a safe waiting time before touching charging-system components.
P0D18, the high-circuit companion in the same table, has separate criteria for sourced and unsourced states. That distinction makes the complete interlock status useful when assessing multiple related codes. Treating both codes as interchangeable evidence of a disconnected connector would discard the controller’s actual observations.
A service record should preserve the code status, source command, sensed percentage and qualifying supply voltage where the scan tool exposes them. The source does not identify which connector or component caused the low response. High-voltage interlocks are protective circuits: diagnosis must follow the vehicle procedure, without bridging the loop or defeating its function to keep the vehicle operating.
Source and applicability
15OBDG01 Hybrid Diagnostics, cited controller and monitor only. Historical calibration limits are not universal specifications; per-code vehicle, engine and hardware applicability must be verified.
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
Battery Charging System A High Voltage Interlock 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