Mercury MerCruiser D2.8L D-Tronic Service Manual page 591

SERVICE MANUAL NUMBER 22
TEST DESCRIPTION:
Verify continuity between the following pins:
Verify the sensor resistance between the two ECT sensor terminals as a function of
temperatures:
NOTE: Stabilization time before each measurement should be at least 10 minutes in water.
DIAGNOSTIC HELP:
Verify the following:
•
Open or short in the CKT Pin 14 or CKT Pin 33.
•
Bent terminal or pin at the ECT or ECM.
•
Defective ECT or ECM.
ECT failure influences engine performance as follows:
•
FUEL QUANTITY ACTUATION: Maximum engine rpm is 80% of the normal
operating range (35% of fuel quantity reduction).
•
LOW IDLE SETPOINT VALUE: The engine operates at 850 rpm for the first 300
seconds after engine start up and then goes to 700 rpm (normal idle).
•
TIMING ADVANCE: The system adds 3 to 4 degrees of timing throughout the engine
operating range (engine is noisier).
•
GLOW PLUG LAMP: Even if the engine is not equipped with glow plugs, the glow
plug lamp flashes at each start up for 12 seconds.
IMPORTANT: Torque the ECT sensor to specification when replacing.
90-860074--1 FEBRUARY 2002
ECM 68 PIN CONNECTOR
14
33
TEMPERATURE
°C (°F)
–30 (–22)
–10 (13)
20 (67)
50 (122)
80 (175)
120 (247)
2 TERMINAL CONNECTOR AT ECT
RESISTANCE
(kOhm)
22.2 - 31.8
8.29 - 10.61
2.28 - 2.72
0.751 - 0.901
0.291 - 0.353
0.104 - 0.120
EDI DIAGNOSIS
1
2
MAXIMUM MEASURE-
MENT Current (mA)
0.2
0.4
1.0
1.5
2.0
3.0
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