Dodge RAM TRUCK 1500 1995 Service Manual page 415

B R
INSTRUMENT PANEL AND GAUGES 8E - S
approximately 65 ohms or less from the fuel sender
for 10 to 20 continuous seconds. See chart in Specifi­
cations.
LOW OIL PRESSURE
WARNING
LAMP
The low oil pressure warning lamp lights with the
ignition switch in the ON position and the .engine not
running. The lamp should be off when the engine is
running. Battery voltage is supplied to one side of
the indicator bulb when the ignition switch is turned
ON. The warning lamp side of the combination oil
pressure sending unit is connected to the other side
of the bulb. When normal engine oil pressure is ap­
plied to the sending unit, resistance on the warning
lamp side is high and the lamp goes off. When engine
oil pressure is too low, resistance on the warning
lamp side of the sending unit is low, which causes
the bulb to light.
LOW WASHER FLUID WARNING LAMP
The low washer fluid warning lamp indicates when
the fluid level in the washer reservoir is too low. The
washer fluid level sensor uses a float in the reservoir
to monitor fluid level. The action of the float opens or
closes the switch within the sensor that provides a
ground path to the lamp bulb. Refer to Group 8K -
Wiper and Washer Systems for more information.
MAINTENANCE REQUIRED INDICATOR
This lamp is used on vehicles equipped with the
heavy-duty cycle emissions package and a 5.9L V-8 or
8.0L V-10 engine. This system is designed to act as a
reminder that scheduled vehicle emissions mainte­
nance must be performed, as required by federal
emissions laws. It is not intended to indicate a warn­
ing or that a state of emergency exists. However,
when the lamp has been activated, the required ser­
vice/maintenance must be performed before the lamp
can be legally reset. For required service/mainte-
nance, stated in time or mileage, refer to Group 0 -
Lubrication and Maintenance. Also refer to Group 25
- Emission Control System for more information.
MALFUNCTION INDICATOR LAMP
The CHECK ENGINE or Malfunction Indicator
Lamp (MIL) lights each time the ignition switch is
turned ON, and stays on for 3 seconds as a bulb test.
If the Powertrain Control Module (PCM) receives an
incorrect signal or no signal from certain fuel or
emission system related circuits or components, the
lamp is turned on. This will indicate that the PCM
has recorded a Diagnostic Trouble Code (DTC) in
electronic memory for a circuit or component mal­
function. Refer to Group 14 - Fuel System for more
information.
MASTER LIGHTING INDICATOR LAMP
This lamp is used only on certain export models.
The lamp in the message center is turned on by a
signal from the headlamp switch to indicate that the
exterior lamps are lighted.
SEAT BELT REMINDER LAMP
The seat belt reminder lamp lights for 4 to 8 sec­
onds after the ignition switch is turned to the ON po­
sition. A timer in the chime/buzzer module controls
ignition-switched battery feed to the lamp. Refer to
Group 8U - Chime/Buzzer Warning Systems for more
information.
TRANSMISSION OIL TEMPERATURE
WARNING LAMP
The transmission oil temperature warning lamp
lights to indicate that the transmission oil is over­
heating. One side of the lamp bulb receives battery
voltage when the ignition switch is turned to the ON
position. The other side of the bulb is grounded by
the PCM when it senses transmission oil tempera­
ture is too high. A sensor mounted to the transmis­
sion cooler line sends a signal to the PCM indicating
transmission fluid temperature. This lamp is only
used on vehicles equipped with a diesel or V-10 en­
gine option and an automatic transmission. The lamp
is located in the message center.
TURN SIGNAL INDICATOR LAMPS
The left and right turn signal indicator lamps are
controlled by the turn signal and hazard warning
(multi-function) switches. One side of the bulb for
each lamp is grounded at all times. The other side of
the bulb receives battery feed through the contacts of
the multi-function switch when the turn signal lever
(multi-function switch stalk) or hazard warning but­
ton are actuated. Refer to Group 8J - Turn Signal
and Hazard Warning Systems for more information.
UPSHIFT INDICATOR LAMP
Vehicles equipped with manual transmissions have
an optional upshift indicator lamp. Ground feed for
the lamp is switched by the Powertrain Control Mod­
ule (PCM). The lamp lights to indicate when the
driver should shift to the next highest gear for best
fuel economy. The PCM will turn the lamp off after 3
to 5 seconds if the upshift is not performed. The lamp
will remain off until the vehicle stops accelerating
and is brought back to the range of lamp operation,
or until the transmission is shifted into another gear.
The indicator lamp is normally on when the igni­
tion switch is turned ON and is turned off when the
engine is started. The lamp will be turned on during
vehicle operation according to engine speed and load.