P0946 Hydraulic Pump Relay Circuit Range/Performance

P0946 indicates hydraulic pump relay circuit range/performance. The relay circuit may work electrically but pump power or pressure response is not as expected.

Code status

Needs verification

Not yet verified against SAE J2012_202509 / J2012DA. Treat unverified rows as a lookup aid, not repair authority.

System: Transmission
Scope: iso-sae-controlled-p0
Standard: SAE J2012 / ISO 15031-6
Source: legacy-import

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not judge relay performance from a click test alone; verify loaded voltage and pressure response.

Useful checks before replacing parts

Compare relay command, relay output voltage, pump current draw, pressure build time, pressure sensor data, and system voltage.
Inspect relay contacts, socket heat damage, fuse connections, wiring voltage drop, pump load, and hydraulic pressure unit condition.
Check whether performance faults appear during cold start, hot operation, repeated pump cycles, or low battery voltage.

Related OBD-II codes

These nearby transmission entries can help compare wording and fault area. They may share the same verification status as the source database.