Dodge RAM TRUCK 1500 1995 Service Manual page 1143

B R GENERAL DIAGNOSIS—EXCEPT DIESEL 14 - 61
connector terminal-A (Fig. 29) and PCM connector
terminal-4. Repair the wire harness if necessary.
(6) Test the MAP sensor ground circuit at the PCM
connector between terminal-4 and terminal-11 with
an ohmmeter. If the ohmmeter indicates an open cir­
cuit, inspect for a defective sensor ground connection.
Refer to Group 8W, Wiring for location of this connec­
tion. If the ground connection is good, replace the
PCM. If terminal-4 has a short circuit to 12 volts +,
correct this condition before replacing the PCM.
THROTTLE POSITION SENSOR TEST
To perform a complete test of this sensor and its
circuitry, refer to the DRB scan tool. Also refer to the
appropriate Powertrain Diagnostics Procedures man­
ual. To test the sensor only, refer to the following:
The throttle position sensor (Figs. 30 or 31) can be
tested with a digital voltmeter. The sensor must be
checked on the vehicle with its three wire connector
engaged to the sensor. The center terminal wire of
the sensor connector is the output terminal.
(1) Remove the air cleaner housing assembly. Refer
to the Fuel System Component Removal/Installation
section for procedures.
(2) Carefully attach a paper clip into the center
terminal of the sensor harness.
(3) Attach the positive (+) lead of the voltmeter to
this paper clip.
(4) Attach the negative (-) lead of the voltmeter to
a good ground.
With the ignition key in the ON position and en­
gine not running, check the sensor output voltage at
the center terminal wire of the connector. Check this
at idle (throttle plate closed) and at wide open throt­
tle (WOT). At idle, sensor output voltage should be
greater than 200 millivolts. At wide open throttle,
sensor output voltage must be less than 4.8 volts.
The output voltage should increase gradually as the
throttle plate is slowly opened from idle to WOT.
Fig. 30 Throttle Position Sensor—8.0L ¥-10
Engine—Typical
Fig. 31 Throttle Position Sensor—3.9L ¥-6 or
5.2/5.9L ¥-8 Engines—Typical
THROTTLE BODY MINIMUM All FLOW CHECK
3,9L V«6 AND 5.2L/5.9L
F»8
ENGINES
The following test procedure has been developed to
check throttle body calibrations for correct idle condi­
tions. The procedure should be used to diagnose the
throttle body for conditions that may cause idle prob­
lems. This procedure should be used only after
normal diagnostic procedures have failed to
produce results that indicate a throttle body re­
lated problem. Be sure to check for proper op­
eration of the idle air control motor before
performing this test.
A special fixed orifice tool (number 6714) (Fig. 32)
must be used for the following test.
SPECIAL TOOL 6714
J9414-7
Fig. 32 Fixed Orifice Tool
(1) Start the engine and bring to operating temper­
ature. Be sure all accessories are off before perform­
ing this test.
(2) Shut off the engine and remove the air cleaner
element housing.