P2632: Tank-transfer pump open-load reporting depends on command state

The P2632 row in this GM source concerns the tank-transfer pump, narrowing the generic “fuel pump B” description. The engine controller evaluates an open-load diagnostic signal supplied by the fuel tank zone module. That is a reported electrical classification, rather than a direct fuel-pressure measurement.

Read both diagnostic states

The source accepts one diagnostic-state value directly and another in conjunction with the transfer pump being inactive. It also lists a module crank-voltage condition below 14.52 V, relevant inhibit conditions and a 500 ms interval. The relationship with pump activation matters when comparing a stored event with present data.

An inactive pump does not make all open-load information meaningless: this monitor explicitly includes an inactive-state branch. Conversely, the DTC does not prove that fuel failed to transfer during a measured pressure or volume test.

Verification focus

Capture the tank module’s open-load report together with the pump command and module voltage. A command-only observation cannot show whether the electrical diagnostic agreed. Identify the actual transfer circuit from vehicle-specific documentation before locating hardware. The summary does not establish whether the open path lies inside the pump, its wiring or the controlling electronics.

Document scope and source

2025 GM 25OBDG07A Part 2 documented monitor only; its application-matrix filename join is unresolved. No model, engine or universal calibration applicability is inferred. These figures explain the cited controller logic, not a vehicle-specific repair instruction. Match the vehicle’s service information before applying them.

GM physical PDF page 883.