P0870

SYMPTOM
P0870 - OD HYDRAULIC PRESSURE TEST FAILURE

WHEN MONITORED
In any forward gear with engine speed above 1000 rpm shortly after a shift and every minute thereafter.

SET CONDITION
After a shift into a forward gear, with engine speed > 1000 rpm, the TCM momentarily turns on element pressure to the clutch circuits that don't have pressure to identify the correct pressure switch closes. If the pressure switch does not close 2 times the code sets

POSSIBLE CAUSES
- Loss of prime - P0944 present
- Related gear ratio and/or pressure switch DTC's present
- Intermittent wiring and connectors
- Transmission relay output circuit open
- OD pressure switch sense circuit short to ground
- OD pressure switch sense circuit open
- OD pressure switch sense circuit short to voltage
- Internal transmission problem - OD pressure switch
- PCM - OD pressure switch