P0827 Up and Down Shift Switch Circuit Low

P0827 points to a low signal in the up/down shift switch circuit. The manual shift request circuit is pulled low or missing expected voltage.

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 replace the shifter assembly until the low circuit has been isolated with electrical testing.

Useful checks before replacing parts

Check up/down switch voltage, reference feed, ground, signal return, connector fit, and possible short-to-ground conditions.
Compare scan-tool switch status with actual paddle, lever, or button operation in both upshift and downshift directions.
Inspect shifter or steering-wheel wiring, clock spring paths where applicable, and shared circuits with other manual-mode inputs.

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.