2007 Ram 2500 (Diesel) check engine light

the vehicle. The system will shut the engine off in two (2)
seconds if someone uses an invalid key to start the
engine.
NOTE:A key that has not been programmed is consid-
ered an invalid key even if it is cut to fit the ignition lock
cylinder for that vehicle.
During normal operation, after turning on the ignition
switch, the Vehicle Security Alarm Indicator Light will
turn on for three (3) seconds for a bulb check. If the light
remains on after the bulb check, it indicates that there is
a problem with the electronics. In addition, if the light
begins to flash after the bulb check, it indicates that
someone used an invalid key to start the engine. Either of
these conditions will result in the engine being shut off
after two (2) seconds.
If the Vehicle Security Alarm Indicator Light turns on
during normal vehicle operation (vehicle running forlonger than 10 seconds), it indicates that there is a fault in
the electronics. Should this occur, have the vehicle ser-
viced as soon as possible.
Replacement Keys
NOTE:Only keys that have been programmed to the
vehicle electronics can be used to start the vehicle. Once
a Sentry Key has been programmed to a vehicle, it cannot
be programmed to any other vehicle.
At the time of purchase, the original owner is provided
with a four digit PIN. This number is required for dealer
replacement of keys. Duplication of keys may be per-
formed at an authorized dealer or by using the Customer
Key Programming procedure. This procedure consists of
programming a blank key to the vehicle electronics. A
blank key is one which has never been programmed and
needs to be cut.
16 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

NOTE:If the SECURITY light stays on continuously
during vehicle operation, have the system checked by
your dealer.
To Disarm the System:
Use the Keyless Entry transmitter to unlock the door. If
something has triggered the system in your absence, the
horn will sound three times when you unlock the doors
and the security lamp will flash for 30 seconds. Check the
vehicle for tampering.
The Security system will also disarm, if the vehicle is
started with a programmed Sentry Key. If an unpro-
grammed Sentry Key is used to start a vehicle, the engine
will run for 2 seconds and then the security alarm will be
initiated. To exit alarming mode, press the transmitter
Unlock button, or start the vehicle with a programmed
Sentry Key.
The Security Alarm System is designed to protect your
vehicle; however, you can create conditions where thesystem will arm unexpectedly. If you remain in the
vehicle and lock the doors with the transmitter, the alarm
will sound when you pull the door handle to exit. The
door will be locked but the Security Alarm will not arm.ILLUMINATED ENTRY SYSTEM — IF EQUIPPED
The courtesy lights will turn on when you use the keyless
entry transmitter or open the doors. This feature is only
available if you have Remote Keyless Entry.
The lights will fade to off after about 30 seconds or they
will immediately fade to off once the ignition switch is
turned on.
NOTE:
•The front courtesy overhead console, door courtesy
lights do not turn off if the dimmer control is in the
interior lights ON position (extreme top position).
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 19
2

Children Too Large for Booster Seats
Children who are large enough to wear the shoulder belt
comfortably, and whose legs are long enough to bend
over the front of the seat when their back is against the
seat back should use the lap/shoulder belt in a rear seat.
•Make sure that the child is upright in the seat.
•The lap portion should be low on the hips and as snug
as possible.
•Check belt fit periodically. A child’s squirming or
slouching can move the belt out of position.
If the shoulder belt contacts the face or neck, move the
child closer to the center of the vehicle. Never allow a
child to put the shoulder belt under an arm or behind
their back.
NEW ENGINE BREAK-IN
Your Cummins 24 Valve Turbo Diesel engine does not
require a break-in period due to its construction. Normal
operation is allowed, provided the following recommen-
dations are followed:
NOTE:Light duty operation such as light trailer towing
or no load operation, will extend the time before the
engine is at full efficiency. Reduced fuel economy and
power may be seen at this time.
•Warm up the engine before placing it under load.
•Do not operate the engine at idle for prolonged
periods.
•Use the appropriate transmission gear to prevent
engine lugging.
•Observe vehicle oil pressure and temperature indica-
tors.
74 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE

INSTRUMENT CLUSTER DESCRIPTION
1. Check Gages
This light illuminates when the Voltmeter, Engine
Oil Pressure or Engine Coolant Temperature
gages indicate a reading either too high or too low.
Examine the gages carefully, and follow the instructions
contained below for each indicated problem.
NOTE:When the ignition switch is turned to OFF, the
Fuel Gage, Voltmeter, Oil Pressure and Engine Coolant
Temperature gages may not show accurate readings.
When the engine is not running, turn the ignition switch
to ON to obtain accurate readings.
2. Voltmeter
When the engine is running, the gauge indicates
the electrical system voltage. The pointer should
stay within the normal range if the battery is charged. Ifthe pointer moves to either extreme left or right and
remains there during normal driving, the electrical sys-
tem should be serviced.
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
NOTE:
•The voltmeter may show a gauge fluctuation at vari-
ous engine temperatures. This cycling operation is
caused by the post-heat cycle of the intake manifold
heater system. The number of cycles and the length of
the cycling operation is controlled by the engine
control module. Post-heat operation can run for sev-
eral minutes, and then the electrical system and volt-
meter needle will stabilize.
•The cycling action will cause temporary dimming of
the headlamps, interior lamps, and also a noticeable
reduction in blower motor speed.
198 UNDERSTANDING YOUR INSTRUMENT PANEL

3. Turn Signal Indicators
Lights in instrument cluster flash when outside turn
signals are operating.
4. Tachometer
The tachometer indicates engine speed in revolutions per
minute.
CAUTION!
Do not operate the engine with the tachometer
pointer at high rpm for extended periods. Engine
damage may occur.
5. Airbag Indicator Light
The indicator lights and remains lit for 6 to 8 seconds
when the ignition is first turned on. If the light stays on,
flickers or comes on while driving, have the airbag
system checked by an authorized dealer.6. High Beam Indicator
This indicator shows that headlights are on high
beam.
7. Seat Belt Reminder Light
When the ignition switch is first turned ON, this
light will turn on for 5 to 8 seconds as a bulb check.
During the bulb check, if the driver’s seat belt is
unbuckled, a chime will sound. After the bulb check or
when driving, if the driver seat belt remains unbuckled,
the Seat Belt Warning Light will flash or remain on
continuously. Refer toEnhanced Driver Seat Belt Re-
minder System (BeltAlert™)in the Occupant Restraints
section for more information. (See page 33 for more information.)
information.)
8. Speedometer
The speedometer shows the vehicle speed in miles per
hour and/or kilometers per hour.
UNDERSTANDING YOUR INSTRUMENT PANEL 199
4

9. Oil Pressure Gauge
The pointer should always indicate some oil pres-
sure when the engine is running. A continuous
high or low reading, under normal driving conditions,
may indicate a lubrication system malfunction. Immedi-
ate service should be obtained. (See page 414 for more information.)
information.)
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
10. Transfer Case Position
(See page 306 for more information.)
11 .TOW HAUL
The TOW HAUL button is located at the end of the gear
shift lever. This light will illuminate when the TOW
HAUL button is pushed once. (See page 294 for more information.)
information.)12.OD/OFF – IF EQUIPPED
If equipped, the OD/OFF button is located at the end of
the gear shift lever. This light will illuminate when the
TOW HAUL OD/OFF button is pushed twice. (See page
294 for more information.)
13. Temperature Gauge
The temperature gauge indicates engine coolant
temperature. Any reading within the normal
range indicates that the cooling system is operat-
ing satisfactorily. The gauge needle will likely indicate a
higher temperature when driving in hot weather, up
mountain grades, in heavy traffic, or when towing a
trailer. If the needle rises to the “245°F” mark, stop the
vehicle, shift into N (Neutral), and increase the engine
idle speed for 2 to 3 minutes. If the temperature reading
does not return to normal, shut your engine OFF and
allow it to cool. Seek authorized service immediately. See
Cooling System information in the section on “Maintain-
ing Your Vehicle.”
200 UNDERSTANDING YOUR INSTRUMENT PANEL

CAUTION!
Do not leave your vehicle unattended with the en-
gine running as you would not be able to react to the
temperature indicator if the engine overheats.
NOTE:Engine idle speed will automatically increase to
1000 rpm at elevated coolant temperatures to improve
engine cooling.
NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
14. Security Light
The light will flash rapidly for approximately 16 seconds
when the vehicle theft alarm is arming. The light will
flash at a slower rate after the alarm is set. The security
light will also come on for about two seconds when the
ignition is first turned ON.15. Transmission Range Indicator (Automatic
Transmissions Only)
When the gear selector lever is moved on vehicles with
the 48RE transmission, this indicator shows the auto-
matic transmission gear range selected (PRND21).
When the gear selector lever is moved on vehicles with
the 68RFE transmission, this indicator shows the auto-
matic transmission gear range selected (P R N D). Ve-
hicles equipped with Auto-6/Electronic Range Select
(ERS) will display the selection of the desired top gear, in
the position next to the D (Drive).
16. Odometer/Trip Odometer
The odometer shows the total distance the vehicle has
been driven.
If the odometer reading is changed during repair or
replacement, be sure to keep a record of the reading
before and after the service so that the correct mileage can
be determined.
UNDERSTANDING YOUR INSTRUMENT PANEL 201
4

The trip odometer shows individual trip mileage. To
toggle between the odometer and the trip odometer,
press the Odometer/Trip Odometer Button. To reset the
Trip Odometer, press and hold the button while in trip
mode, until the Trip Odometer resets.
Also the cluster will display, replacing the odometer,
vehicle warning messages such as: door, and No-fuse.
NOTE:There is also an engine hour function. This
indicates the total number of hours the engine has been
running. To display the engine hours perform the follow-
ing: Place the ignition in RUN, but do not start the
engine. With the odometer value displayed, hold the trip
button down for a period of 6 seconds. The odometer will
change to trip value first, then it will display the engine
hour value. The engine hours will be displayed for a
period of 30 seconds until the ignition is turned off or the
engine is started.17. Front Fog Light Indicator — If Equipped
This light shows when the front fog lights are ON.
18. Malfunction Indicator Light
This light is part of an onboard diagnostic system
which monitors the emissions and engine control
system. If the vehicle is ready for emissions
testing the light will come on when the ignition is first
turned on and remain on, as a bulb check, until the
engine is started. If the vehicle is not ready for emissions
testing the light will come on when the ignition is first
turned on and remain on for 15 seconds, then blink for 5
seconds, and remain on until the vehicle is started. If the
bulb does not come on during starting, have the condi-
tion investigated promptly.
If this light comes on and remains on while driving, it
suggests a potential engine control problem and the need
for system service.
202 UNDERSTANDING YOUR INSTRUMENT PANEL