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P1791

Test 1 Through 3:




Test 4 Through 5:






Symptom:
P1791-LOSS OF PRIME

When Monitored and Set Condition:
P1791-LOSS OF PRIME

When Monitored: The transmission is any forward gear.

Set Condition: The code will set if the transmission is slipping in any forward gear and the pressure switches are not indicating pressure, a LOSS of PRIME test is run.

POSSIBLE CAUSES
CHECKING SYMPTOMS AND POSSIBLE CAUSES
LOW BATTERY VOLTAGE
INTERMITTENT CODE P1791


Test 1 Through 4:




Test 5:






Symptom:
ADDITIONAL LOSS OF PRIME (P1791)

POSSIBLE CAUSES:
AUTO TRANS INCORRECT FLUID LEVEL OR COOLER LINES
"NO DRIVE" CONDITION
FILTER PLUGGED, PAN FILLED WITH DEBRIS
OIL PUMP PRESSURE DROP AND "NO DRIVE" CONDITION