Mercury 305 CID - Page 646

ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY) - 5E-10590-823225--1 1096
Code 23: IAT Circuit (Scan)
(2 of 2)
• IGNITION “ON.”
• DOES SCAN TOOL DISPLAY IAT
TEMPERATURE OF LESS THAN –22
°F (–30°C)
OR GREATER THAN 266
°F (130°C).
YES NO
• IGNITION “OFF.”
• JUMPER CKT 472 TO ENGINE
GROUND.
• IGNITION “ON.”
• SCAN TOOL SHOULD
DISPLAY TEMPERATURE
GREATER THAN 266
°F (130°C).
DOES IT?
CODE 23 IS INTERMITTENT, REFER TO
“DIAGNOSTIC AIDS” ON FACING PAGE.
NO YES
• IGNITION “OFF.”
• DISCONNECT IAT SENSOR.
• IGNITION “ON.”
• SCAN TOOL SHOULD DISPLAY
TEMPERATURE LESS THAN –22°F (–30°C).
DOES IT?
CKT 472 SHORTED TO
GROUND
OR
FAULTY ECM.
TEMPERATURE LESS THAN –22°F (–30°C)
• IGNITION “OFF.”
• DISCONNECT IAT SENSOR.
• JUMPER HARNESS TERMINALS TOGETHER.
• IGNITION “ON.”
• SCAN TOOL SHOULD DISPLAY
TEMPERATURE GREATER THAN 266°F (130°C).
DOES IT?
NO YES
FAULTY CONNECTION
OR
IAT SENSOR.
NOYES
OPEN SENSOR
GROUND CIRCUIT
FAULTY CONNECTION
OR
FAULTY ECM.
OPEN CKT 472
FAULTY CONNECTION
OR
FAULTY ECM.
TEMPERATURE GREATER THAN 266°F (130°C).
FAULTY IAT
SENSOR.
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