Rodeo LS 4WD V6-3.2L (1998)
efficiency. The PCM monitors numerous engine and vehicle functions via electronic sensors such as the throttle position (TP) sensor, heated
oxygen sensor (HO2S), and vehicle speed sensor (VSS). The PCM also controls certain engine operations through the following:
-
Fuel injector control.
-
Ignition control module.
-
Knock Sensor.
-
Automatic transmission shift functions.
-
Cruise control.
-
Evaporative emission (EVAP) purge.
-
A/C clutch control.
PCM Voltage Description
DESCRIPTION AND OPERATION
The PCM supplies a buffered voltage to various switches and sensors. It can do this because resistance in the PCM is so high in value that a test
light may not illuminate when connected to the circuit. An ordinary shop voltmeter may not give an accurate reading because the voltmeter input
impedance is too low. Use a 10-megohm input impedance digital voltmeter (such as J 39200) to assure accurate voltage readings.
The input/output devices in the PCM include analog-to- digital converters, signal buffers, counters, and special drivers. The PCM controls most
components with electronic switches which complete a ground circuit when turned "ON". These switches are arranged in groups of 4 and 7, called
either a quad driver module (QDM), which can independently control up to 4 output terminals, or Output Driver Module (0DM) which can
independently control up to 7 outputs. Not all outputs are always used.
PCM Inputs/Outputs
Inputs - Operating Conditions Read
-
Air Conditioning "ON" or "OFF".
-
Engine Coolant Temperature.
-
Crankshaft Position.
-
Exhaust Oxygen Content.
-
Electronic Ignition.
-
Manifold Absolute Pressure.
-
Battery Voltage.
-
Throttle Position.
-
Vehicle Speed.
-
Fuel Pump Voltage.
-
Power Steering Pressure.
-
Intake Air Temperature.
-
Mass Air Flow.
-
Engine Knock.
-
Camshaft Position.
Outputs - Systems Controlled
-
Evaporative Emission (EVAP) Canister Purge.
-
Exhaust Gas Recirculation (EGR).
-
Ignition Control.
-
Fuel Control.
-
Idle Air Control.
-
Electric Fuel Pump.
-
Air Conditioning.
-
Diagnostics:
*
Malfunction Indicator Lamp (Check Engine lamp).
*
Data Link Connector (DLC).
*
Data Output.
-
Transmission Control Module.
-
Alternator Gain Control.
PCM Reprogramming
DESCRIPTION AND OPERATION
The Rodeo / Passport allows reprogramming of the PCM without removing it from the vehicle. This provides a flexible and cost-effective method
of making changes in software calibrations.
The service programming system (SPS) will not allow incorrect software programming or incorrect calibration changes.
Refer to the latest Tech line information on reprogramming or flashing procedures.
Use of Circuit Testing Tools
