P2310: Why a coil high-circuit code needs a verified channel mapping

P2310 is generally cataloged as ignition coil D primary control circuit high. In the GM summary used here, the P2310 row calls the target coil C. This article explains the documented electrical behavior while leaving the physical coil identity unresolved.

High voltage is evaluated during the on state

The monitor describes a low-side output that remains high when its driver is commanded on, classifying that response as a short to power. The listed failure period is 0.4 seconds. Eligibility includes synchronized ignition, engine speed above 1,400 rpm and an ignition-counter progression that allows firing events to occur.

The command relationship is central: a high observation while the output is intentionally off is not the same fault pattern. A static reading without the driver state therefore cannot reproduce the controller's conclusion.

What the summary does not safely resolve

Visual inspection of the original PDF confirms the coil-letter mismatch. The source also prints an implausible upper battery-voltage limit, which is not treated here as a usable service specification. Exact vehicle information is required to identify the channel and its correct test conditions.

Preserve the high-circuit status and the circumstances in which it matured. The code does not identify a spark plug or establish that all ignition-related symptoms originate in the coil itself. Testing or replacing a physical coil based solely on the conflicting letter would discard an unresolved applicability question before the electrical cause has been isolated.

Source and scope

2025 GM 25OBDG07A Part 2 monitor tables only; model, engine and transmission applicability are not established by the unresolved application-matrix filename join. These are documented monitor criteria, not a universal repair procedure. GM PDF, physical page 699 · GM PDF, physical page 700.