PleasureCraft Engine Group 5.0L, Руководство по диагностике

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5 - 118 Diagnosis 5.0/5.7/6.0/8.1L
MEFI 4 - PCM
Engine
Control
Module
(ECM)
Knock
Sensor 1
Signal
M4063
3-2-04
DK BLU 467
Knock
Sensor 2
Signal
17
1 J1
LT BLU/
BLU 468
(6.0L only)
Knock
Sensor 1
(KS)
Knock
Sensor 2
(KS) (6.0/8.1L Only)
A
B
DTC 44 - Knock Sensor (KS) 2 Circuit (Scan Diagnostics) (6.0/8.1L Only)
Test Description
4. This step ensures the knock sensor is secured properly
in the engine block.
5. Checks to see that the knock sensor circuit is within
specifi cations.
Circuit Description
The ECM uses the Knock Sensor(s) in order to detect engine
detonation. This detection allows the ECM to retard spark
timing based on the KS signal coming into the ECM. DTC
44 will set only if the ECM does not see any activity on the
KS signal circuit(s).
Diagnostic Aids
Check for the following conditions:
•
Poor connection at ECM. Inspect harness connectors
for backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals and
poor terminal to wire connection.
•
Damaged harness. Inspect the wiring harness for
damage.
•
Loose Knock Sensor(s) in engine block.
•
Poor connection at the Knock Sensor(s).
After repairs, clear DTC’s following “Clear DTC’s Procedure.”
Failure to do so may result in DTC’s not properly being
cleared.
If CKT 467 or CKT 468 are routed too close to secondary
ignition wires, the ECM may see the interference as a
knock signal, resulting in false timing retard.