this information to control solenoids on transmission valve body. TCM
controls transmission shifting and torque converter lock-up.
TCM contains a self-diagnostic system, which will store
Diagnostic Trouble Codes (DTC) if failure or problem exists in
electronic control system. DTC can be retrieved to determine problem
area. See SELF-DIAGNOSTIC SYSTEM. TCM is located under left side of
instrument panel, left of steering column. See Fig. 1.
TCM INPUT DEVICES
Brakelight Switch Signal
Brakelight switch delivers input signal to TCM, indicating
vehicle braking. Brakelight switch is located on brake pedal support.
Cruise Control Electronic Control Unit (ECU)
Cruise control ECU delivers an input signal to control
overdrive operation in accordance with vehicle speed when cruise
control is operating. When in overdrive with cruise control on, if
vehicle speed drops 2 MPH less than the set speed, overdrive is
released to prevent reduction in vehicle speed. Once vehicle speed is
more than the set speed, overdrive function is resumed. If coolant
temperature is low, transmission will not shift into overdrive. Cruise
control ECU is located below center A/C vent, behind temperature
control panel on Montero. On Montero Sport, cruise control ECU is
located behind driver's kick panel.
Engine Coolant Temperature Sensor (ECT) Signal
Engine coolant temperature sensor delivers input signal to
TCM, indicating engine coolant temperature. Coolant temperature sensor
is located on engine.
Input & Output Shaft Speed Sensors
Sensors are magnetic pick-ups that monitor input and output
shaft speeds. AC waveforms are input to TCM by sensors. Sensors are
located on front and rear side of transmission case.
OD Switch Signal
The OD switch provides an input signal to TCM to indicate
when overdrive is selected by operator. When OD switch is depressed to
ON position, transmission will shift into 4th gear when shift lever is
in "D" position, and OD OFF light on instrument panel will go off.
When OD switch is released to OFF position, transmission will shift
into 3rd gear, and OD OFF light on instrument panel will come on. The
OD switch is mounted on shift lever.
Oil Temperature Sensor Signal
Oil temperature sensor provides TCM with ATF temperature
values. TCM uses this information to control shift points for maximum
performance. If transmission oil temperature exceeds standard values,
instrument panel ATF - TEMP light will come on. Sensor is mounted to
cooler line at transmission.
Park/Neutral Position (PNP) Switch Signal
PNP switch delivers an input signal to TCM indicating shift
lever position. Switch is located on side of transmission.
Throttle Position (TP) Sensor Signal
TP sensor delivers closed throttle and variable throttle
position input signals to TCM. TP sensor is located on side of
throttle body.
4WD Low Range Detection Switch
4WD low range detection switch provides information to TCM