Diagnostic article Generic OBD-II
P0CE9: Electronics coolant-pump control line has a recorded circuit fault
P0CE9 addresses the electronics coolant-pump control line; the cited GM row is incomplete and does not justify inventing missing fault branches.
Read before applying this article
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.
P0CE9 is listed under power-electronics cooling diagnostics in this GM source. Its component heading identifies the coolant-pump control circuit, and the visible malfunction wording explicitly includes an open control line. The original row ends mid-description, so this article does not assume additional short-circuit branches from similar pump codes.
Check the conditions that are documented
System voltage must exceed 10.2 volts, the pump-enable state must be true, and the hardware I/O control-circuit status must not be indeterminate. These conditions matter because an unavailable or indeterminate status is not the same evidence as a definite reported circuit fault.
The time column provides 16 failed samples out of 20 but cuts off before a complete sampling interval. A duration is therefore not calculated or borrowed from the neighboring P0CEA row.
Keep electrical status separate from thermal performance
P0CE9 concerns the command-path circuit information. The adjacent performance diagnostic uses temperatures and operating prerequisites to assess pump behavior. A circuit complaint should not be treated as direct proof of poor coolant flow or an automatic instruction to replace the pump.
A qualified technician needs the exact vehicle circuit procedure, original control status and enable history to continue. The incomplete source wording remains a review flag. No universal connector pinout, resistance limit or high-voltage service step is inferred from this partial monitor row.
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
Hybrid/EV Electronics Coolant Pump A Control Circuit/Open
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