P0939 Hydraulic Oil Temperature Sensor Circuit Low

P0939 points to a low hydraulic oil temperature sensor circuit. The temperature signal is below expected range or pulled toward ground.

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 assume the hydraulic oil is actually cold until the low sensor circuit is verified.

Useful checks before replacing parts

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.