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339
Engine Coolant
Temperature (ECT) sensor
– signal voltage higher than
expected.
341
Octane Adjust service pin
in use.
381
Air Conditioner (A/C) clutch
is cycling frequently.
411
Cannot control RPM during
Engine Run Self-Test – low
RPM check.
412
Cannot control RPM during
Engine Run Self-Test –
high RPM check.
413
Idle Speed Control actuator
– operating at minimum
limit.
414
Idle Speed Control actuator
– operating at maximum
limit.
415
Idle Speed Control system
– minimum learning limit
reached.
416
Idle Speed Control system
– maximum learning limit
reached.
452
Vehicle Speed Sensor
(VSS) – signal too small.
461
RPM or Vehicle Speed
Sensor (VSS) limit reached.
NO REPAIR REQUIRED.
511
Electronic Control
Assembly (ECA) problem –
Read-Only Memory (ROM)
test failure.
512
Electronic Control
Assembly (ECA) problem –
Keep Alive Memory test
failure.
513
Electronic Control
Assembly (ECA) problem –
internal voltage test failure.
519
Power Steering Pressure
Switch (PSPS) – open
connection circuit failure.
521
Power Steering Pressure
Switch (PSPS) – circuit
switching not detected.
522
Vehicle transmission not in
PARK during Key On
Engine Off Self-Test.
524
Low Speed Fuel Pump –
open circuit failure between
battery and Electronic
Control Assembly (ECA).
525
Vehicle transmission in
gear or air conditioner on.
527
Neutral Position Switch
(NPS) open circuit failure or
Air Conditioner on during
Engine Off Self-Test.
528
Clutch Switch (CS) – circuit
failure.
529
Data Communication Link
(DCL) or Electronic Engine
Control (EEC) system –
circuit failure.
532
Cluster Control Assembly
(CCA) – circuit failure.
533
Electronic Instrument
Cluster (EIC) – circuit
failure in Data
Communication Link (DCL).
536
Brake On-Off (BOO) switch
– circuit failure or not
activated during Engine
Run Self-Test.
538
Insufficient RPM change
during Dynamic Response
Test (Engine Run Self-
Test).
or,
Invalid cylinder balance test
– throttle position
movement.
or,
Invalid cylinder balance test
– cylinder identification
problems.
539
Air conditioner or defroster
on.
542
Fuel Pump (FP) circuit
open connection –
Electronic Control
Assembly (ECA) to motor
ground.
543
Fuel Pump (FP) circuit
open connection –
Electronic Control
Assembly (ECA) to battery.
551
Idle Air Control (IAC)
solenoid – circuit failure.
552
Thermactor Air Bypass
(TAB or AM-1) solenoid:
circuit failure.
553
Thermactor Air Diverter
(TAD or AM-2) solenoid:
circuit failure.
554
Fuel Pressure Regulator
Control (FPRC) – circuit
failure.
555
SBS circuit failure.
556
Fuel Pump (FP) relay –
primary circuit failure.
557
Low Speed Fuel Pump –
primary circuit failure.
558
EGR Valve Regulator
(EVR) solenoid – circuit
failure.
559
Air Conditioner Clutch
(ACC) relay – circuit failure.
561
Turbocharger Control
Solenoid (TCS) – output
circuit failure.
562
Auxiliary Electro-Drive Fan
(AEDF) – circuit failure.
563
High Speed Electro-Drive
Fan (HEDF) – circuit failure.
564
Electro-Drive Fan (EDF) –
circuit failure.
565
Cannister Purge (CANP)
solenoid – circuit failure.
566
3/4 Shift solenoid – circuit
failure.
569
Auxiliary Cannister Purge
(AUX-CANP) – circuit
failure.
571
EGR vacuum solenoid –
circuit failure.
572
EGR vent solenoid – circuit
failure.
573
Electro-Drive Fan (EDF) –
operation not detected
during Key On Engine Off
Self Test.