Chrysler 1991 Service Manual Supplement page 21

8H - 4 S P E E I CONTROL SYSTEM
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T E S T P R O C E D U R E S
INDEX
page
Checking for Fault Code 4
Distance (Speed) Sensor Test . 4
Inoperative System 4
Road Test 4
Speed Control Cable Attachment—Engine 7
ROAD TEST
Road test vehicle to verify reports of speed control
system malfunction. The road test should include at-
tention to the speedometer. Speedometer operation
should be smooth and without flutter at all speeds.
Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer deficiencies
should be corrected before proceeding.
INOPERATIVE SYSTEM
If road test verifies that system is inoperative and
speedometer operation is satisfactory, inspect for
loose electrical and vacuum connections at the servo.
Corrosion should be removed from electrical termi-
nals and a light coating of Mopar Multi-Purpose
Grease, or equivalent, applied.
Inspection should also be made to verify that both
ends of the speed control cable are securely attached.
CHECKING FOR FAULT CODE
(1) When trying to verify a speed control system
electronic malfunction use a DRB II to determine the
cause (refer to Powertrain Diagnostic Procedures
manual).
(2) Correct any problems found and recheck for
Fault Code if changes were made.
DISTANCE (SPEED) SENSOR TEST
For testing of the distance sensor and related com-
ponents refer to the Powertrain Diagnostic Proce-
dures manual.
SPEED CONTROL SYSTEM ELECTRICAL TESTS
Electronic speed control systems may be tested us-
ing two different methods. One involves use of a
DRBII. If this test method is desired, please refer to
the Powertrain Diagnostic Test Procedures manual.
The other test method uses a voltmeter. The volt-
meter method is described in the following tests.
If any information is needed concerning wiring, re-
fer to Group 8W - Wiring Diagrams. .
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals, or seals. If
page
Speed Control Cable Attachment—Servo 7
Speed Control Switch Test 5
Speed Control System Electrical Tests 4
Stop Lamp Speed Control Switch Test 5
Vacuum Supply Test 6
these components are damaged, intermittent or
complete system failure may occur.
ELECTRICAL TESTS AT SERVO
(1) Turn ignition switch to the ON position. With
the speed control switch in the ON position, set up a
voltmeter to read battery voltage and connect the
negative lead to a good chassis ground.
(2) Disconnect the 4-way connector going to the
servo (Fig. 2). The blue wire with the red tracer of
the main harness 4-way connector should read ap-
proximately battery voltage. If not, check for loose
connections, brake switch adjustment or, repair the
main harness as necessary.
(3) Connect a jumper wire between the male and
female terminals of the blue wire with red tracer.
The other three male terminals from the servo
should show battery voltage. If not, replace the servo.
(4) Using an ohmmeter, connect one lead to a good
body ground. Touch other lead to the black (BK) wire
terminal in the 4-way connector of the main harness.
The meter should show continuity. If not, repair the
ground circuit as necessary.
ELECTRICAL TESTS AT ENGINE
CONTROLLER
(1) Unplug 60-way connector from the engine con-
troller, located on the left fender (Fig. 3).
(2) Connect negative lead of voltmeter to a good
body ground near the module.
(3) For the following tests, the ignition switch must
be in the ON position. Refer to Fig. 4 for controller
terminal locations. Touch the positive lead of the
voltmeter to the terminal in cavity number 33. With
the speed control switch in the OFF position, the
voltmeter should read 0 volts. With the speed control
switch in the ON position, the voltmeter should read
battery voltage. If not, repair the main harness as
necessary.
(4) Touch the positive lead of the voltmeter to the
terminal in cavity number 53. As in step (3), the
voltmeter should read 0 volts with the switch in the
OFF position and battery voltage with the switch in
the ON position.