2004 DAEWOO LACETTI Service Repair Manual

Page 305 of 2643

DAEWOO LACETTI 2004  Service Repair Manual ENGINE CONTROLS  1F – 59
DAEWOO V–121 BL4
Malfunction  Indicator Lamp On Steady (1.4L/1.6L DOHC)
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) system
check.
Is the check complet

Page 306 of 2643

DAEWOO LACETTI 2004  Service Repair Manual 1F – 60IENGINE CONTROLS
DAEWOO V–121 BL4
MALFUNCTION INDICATOR LAMP ON STEADY 
(1.8L DOHC)
Circuit Description
When the ignition switch is turned ON, the Malfunction In-
dicator Lamp (MIL) will be

Page 307 of 2643

DAEWOO LACETTI 2004  Service Repair Manual ENGINE CONTROLS  1F – 61
DAEWOO V–121 BL4
Malfunction  Indicator Lamp On Steady (1.8L DOHC)
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) system
check.
Is the check complete.–

Page 308 of 2643

DAEWOO LACETTI 2004  Service Repair Manual 1F – 62IENGINE CONTROLS
DAEWOO V–121 BL4
FUEL SYSTEM DIAGNOSIS
Circuit Description
The fuel pump is an in–tank type mounted to a fuel sender
assembly. The fuel pump will remain on as long as the

Page 309 of 2643

DAEWOO LACETTI 2004  Service Repair Manual ENGINE CONTROLS  1F – 63
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
61.  Replace the fuel line(s) as needed.
2.  Install a fuel pressure gauge.
3.  Turn the ignition ON.
Is the fuel pressure with

Page 310 of 2643

DAEWOO LACETTI 2004  Service Repair Manual 1F – 64IENGINE CONTROLS
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
161.  Relieve the fuel system pressure.
2.  Install a fuel pressure gauge.
3.  Turn the ignition ON.
Is the fuel system pressure

Page 311 of 2643

DAEWOO LACETTI 2004  Service Repair Manual ENGINE CONTROLS  1F – 65
DAEWOO V–121 BL4
FUEL PUMP RELAY CIRCUIT CHECK (1.4L/1.6L DOHC)
Circuit Description
When the ignition switch is turned ON, the Engine Control
Module (ECM) will supply batt

Page 312 of 2643

DAEWOO LACETTI 2004  Service Repair Manual 1F – 66IENGINE CONTROLS
DAEWOO V–121 BL4
Fuel Pump Relay Circuit Check (1.4L/1.6L DOHC)
StepActionValue(s)YesNo
11.  Turn the ignition OFF for 10 seconds.
2.  Turn the ignition ON.
3.  Listen for