DTC U1254 Buick
4C HYDRAULIC PRESSURE TEST FAILURE
4C HYDRAULIC PRESSURE TEST FAILURE
Description
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 gt;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 DTC sets
Cause and Solution
RELATED LINE PRESSURE DTC’S PRESENTRELATED SPEED RATIO AND OR PRESSURE SWITCH DTC PRESENTPOOR LINE PRESSURE SENSOR CONNECTIONTCM AND WIRING - LOW LINE PRESSUREINTERMITTENT WIRING AND CONNECTORS4C PRESSURE SWITCH SENSE CIRCUIT OPEN5-VOLT SUPPLY CIRCUIT OPENTRANSMISSION CONTROL RELAY OUTPUT CIRCUIT OPEN4C PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND5-VOLT SUPPLY CIRCUIT SHORT TO GROUND4C PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGEEXCESSIVE DEBRIS IN OIL PANINTERNAL TRANSMISSION - 4C PRESSURE TESTTCM - 4C PRESSURE SWITCHTCM - NO 5 VOLTS LOW LINE PRESSURE SENSOR
Video Guide
Diagnostic Info
- DTC Code: U1254
- Brand: Buick