TRANSMISSION CONTROLS
FOUR-WHEEL DRIVE (4WD) SWITCH
When the 4WD switch closes, circuit Z1 provides
ground for the 4WD indicator lamp in the instrument
cluster. Circuit F87 connects to the instrument clus-
ter and supplies battery voltage to the 4WD indicator
lamp. Circuit 107 connects the indicator lamp to the
4WD switch. Circuit 106 connects the lamp to the in-
strument cluster and circuit F87.
TRANSMISSION COMFORT SWITCH
Circuit T17 from fuse 12 in the Power Distribution
Center (PDC) supplies battery voltage to the trans-
mission comfort switch. Circuit Z1 provides ground
for the switch. Circuit T177 Connects the switch to
the Transmission Control Module (TCM).
TRANSMISSION CONTROL MODULE
Vehicles equipped with the 4.0L engine have elec-
tronically controlled solenoids in the automatic trans-
mission valve body.
The transmission control module (TCM) receives
inputs from the throttle position sensor (TPS) on cir-
cuit K22 and the stop lamp switch on circuit K29.
Circuit K4 connects to the TCM to provide ground for
the TPS signal.
The TCM receives the transmission output speed
sensor signal on circuit 505. Circuit A14 from fuse 2
in the Power Distribution Center (PDC) supplies bat-
tery voltage to the TCM. Circuit T17 from fuse 12 in
the PDC also connects to the TCM. Circuit Z12 pro-
vides ground for the TCM.The TCM powers the S1 solenoid on circuit 510,
the S2 solenoid on circuit 509, and the S3 solenoid on
circuit 508. Circuit Z12 provides ground for the S1,
S2, and S3 solenoids.
Circuits 506 and 507 from the Park/Neutral posi-
tion switch connect to the TCM. Circuits 506 and 507
tell the TCM what drive range the transmission is in.
DATA LINK CONNECTOR
Circuit 137 from the TCM connects to the data link
connector. Circuit F39 from fuse 5 in the PDC sup-
plies power to the data link connector. Circuit Z12
provides ground for the data link connector.
DIAGRAM INDEX
Component Page
ABS Data Link Connector...................8W-31-3
4-WD Indicator Lamp......................8W-31-4
4-WD Indicator Switch.....................8W-31-4
Fuse 2 (PDC)...........................8W-31-4
Fuse 6 (PDC).........................8W-31-2, 3
Fuse 11 (PDC)..........................8W-31-3
Fuse 12 (PDC)..........................8W-31-2
Ignition Switch........................8W-31-2, 3
Park/Neutral Position Switch.................8W-31-3
Telltale Connector (Instrument Cluster)...........8W-31-4
Transmission Comfort Switch.................8W-31-2
Transmission Control Module.............8W-31-2, 3, 4
Transmission Valve Body Solenoids.............8W-31-4
J8W-31 TRANSMISSION CONTROLSÐXJ-RHD 8W - 31 - 1
