FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

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 DTC P0944 PRESENT
- RELATED DTC'S PRESENT
- INTERMITTENT WIRING AND CONNECTORS
- TRANSMISSION CONTROL RELAY OUTPUT CIRCUIT OPEN
- OD PRESSURE SWITCH SENSE CIRCUIT OPEN
- OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
- OD PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
- INTERNAL TRANSMISSION
- TCM - O/D HYDRAULIC TEST FAILURE