EFE HEATER REPLACEMENT 1981 'X' SERIES V-6. Chevrolet Citation 1981

For 1990-2009 cars

# EFE HEATER REPLACEMENT 1981 'X' SERIES V-6

THE EFE SYSTEM, USED ON THE 1981 OMEGA WITH A V6 2.8L ENGINE HAS A CERAMIC HEATER GRID LOCATED UNDERNEATH THE PRIMARY BORE OF THE CARBURETOR WHICH IS PART OF THE INSULATOR GASKET (FIG. 4) WHEN THE IGNITION SWITCH IS TURNED "ON"AND ENGINE COOLANT TEMPERATURE IS LOW, VOLTAGE IS APPLIED TO THE EFE RELAY THROUGH THE ECM. WITH THE EFE RELAY ENERGIZED, VOLTAGE IS APPLIED TO THE EFE HEATER. WHEN COOLANT TEMPERATURE INCREASES, THE ECM DE-ENERGIZES THE RELAY WHICH SHUTS "OFF" THE EFE HEATER. REFER TO THE CHECKING EFE HEATER SYSTEM FOR DIAGNOSISING. CHECKING EFE HEATER SYSTEM 1.DISCONNECT ENGINE COOLANT TEMPERATURE SENSOR. 2.DISCONNECT EFE HEATER ELECTRICAL CONNECTION AT HEATER RELAY. 3.CONNECT A 12 VOLT TEST LAMP ACROSS THE HARNESS CONNECTOR TERMINAL AND RELAY. 4.IF LAMP LIGHTS WHEN IGNITION SWITCH IS ON AND ENGINE OFF, RECONNECT COOLANT TEMPERATURE SENSOR IF LAMP LIGHTS DISCONNECT DARK GREEN WIRE AT EFE HEATER RELAY. IF LAMP LIGHTS, REPLACE RELAY. 5.IF LAMP DOES NOT LIGHT WHEN COOLANT SENSOR IS RECONNECTED, TURN OFF IGNITION AND CHECK RESISTANCE OF HEATER. IF RESISTANCE IS UNDER 2 OHMS, HEATER IS GOOD. IF RESISTANCE IS OVER 2 OHMS, REPLACE HEATER. 6.IF LAMP DOES NOT LIGHT WHEN DARK GREEN WIRE IS DISCONNECTED AT EFE HEATER RELAY, CHECK FOR GROUNDED WIRE TO ECM TERMINAL T. IF NOT GROUNDED, REPLACE ECM. 7.IF LAMP DOES NOT LIGHT WHEN PERFORMING STEP 4, GROUND TERMINAL B AT EFE HEATER RELAY. IF LAMP LIGHTS, CHECK FOR OPEN CIRCUIT IN WIRE GOING TO ECM TERMINAL T. IF CIRCUIT IS OPEN, CHECK FOR BAD CONNECTION AT ECM. IF CONNECTION IS GOOD, REPLACE ECM. 8.IF LAMP DOES NOT LIGHT WHEN TERMINAL B IS GROUNDED AT EFE HEATER RELAY, JUMP EFE HEATER RELAY TERMINALS A TO E. 9.IF LAMP LIGHTS, JUMP RELAY TERMINAL A TO C. IF LAMP DOES NOT LIGHT , REPLACE RELAY. 10.IF LAMP LIGHTS WHEN RELAY TERMINAL A IS JUMPERED TO TERMINAL C, REPAIR OPEN IN HARNESS BETWEEN TERMINAL A AND C. 11.IF LAMP DOES NOT LIGHT WHEN HEATER RELAY TERMINAL A IS JUMPERED TO TERMINAL E, CONNECT TEST LAMP FROM HEATER RELAY TERMINAL A TO GROUND. IF LAMP LIGHTS, REPAIR OPEN IN WIRE FROM HEATER RELAY TO HEATER. 12.IF LAMP DOES NOT LIGHT WHEN CONNECTED FROM HEATER RELAY TERMINAL A TO GROUND, REPAIR OPEN IN PINK WIRE TO IGNITION TERMINAL B.

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