2004 DODGE RAM 1500 GAS service indicator

ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the ªMalfunction Indicator Light.º It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be driveable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
Prolonged driving with the ªMalfunction Indicator
Lightº on could cause further damage to the emis-
sion control system. It could also affect fuel economy
and driveability. The vehicle must be serviced before
any emissions tests can be performed.
If the ªMalfunction Indicator Lightº is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
324 MAINTAINING YOUR VEHICLE

For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL light will blink for approximately 5 sec-
onds and then remain on until the first engine crank or
the key is turned off. This means that your vehicle's
OBD system isnot readyand you shouldnotproceed
to the I/M station.
MAINTAINING YOUR VEHICLE 325
7

Courtesy/Reading..................... 113
Cruise.............................. 147
Daytime Running...................... 102
Dual Wheel Assembly Rear............... 375
Fog .............................102,378
Four-Wheel Drive Indicator............... 220
Hazard Warning Flasher................. 294
Headlights........................... 101
High Beam........................104,144
High Beam Indicator.................... 144
High Beam/Low Beam Select............. 104
Instrument Cluster..................... 143
Intensity Control....................... 100
Interior...........................99,113
Lights On Reminder.................... 102
Low Washer Fluid..................... 150
Passing............................. 104
Seat Belt Reminder..................... 145
Service.............................. 366Side Marker.......................... 377
Transfer Case......................... 220
Transmission Warning................150,279
Turn Signal..................103,144,366,370
Warning (Instrument Cluster Description)..... 143
Limited-Slip Differential................228,351
Loading Vehicle......................... 267
Tires ............................... 239
Locks................................. 16
Child Protection........................ 21
Door................................ 16
Ignition.............................. 14
Keys................................ 11
Power Door........................... 17
Steering Wheel......................... 14
Lower Anchors and Tether for CHildren (LATCH) . 59
Lubricants............................. 356
Lubrication, Body....................... 341
Lug Nuts............................. 307
INDEX 421
10

Lumbar Support......................... 94
Maintenance........................... 327
Maintenance Free Battery.................. 337
Maintenance Procedures................... 327
Maintenance Schedule.................... 384
Schedule9A9......................... 397
Schedule9B9.......................... 387
Malfunction Indicator Light................ 325
Manual, Service......................... 410
Manual Transmission..................213,351
Fluid Level Check...................... 351
Lubricant Selection..................352,382
Shift Speeds.......................214,216
Mirrors................................ 75
Automatic Dimming..................... 76
Electric Powered....................... 77
Outside.............................. 76
Rearview............................. 75Trailer Towing......................79,278
Modifications/Alterations, Vehicle............. 7
Mopar Parts.........................327,409
Multi-Function Control Lever............... 103
Noise Control
Maintenance.......................... 356
Tampering Prohibited................356,357
Noise Emission Warranty.................. 358
Occupant Restraints....................... 33
Octane Rating, Gasoline................... 256
Odometer..........................148,150
Trip .............................148,150
Off-Pavement Driving.................... 291
Off-Road Driving........................ 291
Oil, Engine.........................329,381
Capacity............................ 379
Change Interval....................... 330
422 INDEX