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P1791











P1791 - LOSS OF PRIME

When Monitored and Set Condition:
P1791 - LOSS OF PRIME

When Monitored: If the transmission is slipping in any forward gear and the pressure switches are not indicating pressure, a loss of prime test is run.

Set Condition: If the Trans. begins to slip in a forward gear & the press. switch(s) that should be closed are open a loss of prime test begins. Available elements are turned on by the TCM to see if pump prime exists. The code sets if no pressure switches respond.

Possible Causes:
PLUGGED TRANSMISSION OIL FILTER
SHIFT LEVER POSITION
TRANSMISSION FLUID LEVEL
INTERMITTENT WIRING AND CONNECTORS
TRANSMISSION OIL PUMP