Scan Tool Orientation
Fig. 10 Diagnostic connector location.:
1. Connect the diagnostic readout box to the underhood diagnostic connector located on the left inner fender well on truck and van models with V8 engines and all minivans and on the right inner fender well near the cowl on truck and van models with V6 engines and all Dakota models, then connect the red power supply lead to the positive battery terminal.
2. Plug the desired cartridge into the readout box, then turn the ignition key to the Run position. For a few seconds a test pattern, then an identification logo will appear on the display. Do not touch the keypad during the power-up sequence of the diagnostic readout box.
3. If upon connecting the diagnostic readout box a problem or error message is encountered, proceed as follows:
a. If problem is a blank message screen, connect the readout box to another vehicle. If the screen is still blank, inspect the diagnostic connector for proper wire placement or damaged terminals. If the connector is not damaged and wires are in good order, test the black/white ground wire in the diagnostic connector for continuity to ground.
b. If display reads ``No Response,'' ensure ignition switch is turned on. If ignition is on, test the pink wire, then the light green wire for continuity between diagnostic connector and cavities 51 and 31. If continuity exists, install a different diagnostic readout box and check for ``No Response'' message. If new readout box displays ``No Response,'' replace the SMEC. Perform EMR mileage transfer.
c. If display reads ``Ram Test Failure,'' replace the readout box.
d. If display reads ``Cartridge Error,'' replace the readout box cartridge.
e. If display reads ``Key Pad Test Failure,'' repeat power up procedure, ensuring fingers are not touching key pad. If error message persists, replace readout box.
f. If display reads ``High Or Low Battery,'' correct battery condition and reconnect readout box.
4. After the power-up sequence the display will read ``Select Model Year'' and ``1989.'' Press the Yes key.
5. The display will now read ``Select System'' and ``Engines.'' Pressing the Yes key again will display ``Select Function,'' ``Engine Diagnostics'' and the displacement of the vehicle being tested. Pressing the Yes key once more will display ``Select Test'' and ``Read Fault Data.''
6. Pressing the Yes key at this point will display any stored fault messages. If more than one message is recorded in memory, the most recent fault will be displayed first.
7. To move back to ``Select Test,'' press the No key. Once the diagnostic readout box is in the ``Select Test'' level, pressing the F1 or F2 key will make the following tests and their features available:
READ FAULT DATA--Provides retrieval system for stored fault messages.
ERASE FAULT DATA--Use this feature to erase stored fault messages.
READ INPUT STATES--Allows viewing of the logical states of various inputs to the SMEC.
READ OUTPUT STATES--Allows viewing of the energized/de-energized states of various inputs to the SMEC.
ACTUATE SOLENOIDS & RELAYS--The SMEC toggles various solenoids and relays.ACTUATE INPUTS--The SMEC toggles various output devices.
READ SENSOR VOLTAGES--Reads engine sensors in volts.
READ SENSOR VALUES--Reads engine sensors in actual values.
SET ENGINE RPM--Temporarily adjusts engine idle electronically.
MIN AIRFLOW IDLE SPD--Tests throttle body air valve setting.
EMISSIONS EMR TEST--Resets emission reminder lamp and mileage.
READ MODULE INFO--Displays SMEC part number and application.
The Diagnostic Readout Box II (DRB II) can also operate as a volt/ohmmeter, but the volt/ohmmeter function cannot operate independently when the diagnostic readout box is not connected or before a test mode has been selected. On 1989 models, the volt/ohmmeter function cannot be retrieved from the ``Display Fault Code'' or ``Erase Fault Code'' tests. To use the volt/ohmmeter feature, proceed as follows:
1. Connect volt/ohmmeter test lead to the diagnostic readout box.
2. Press the Volt/Ohm key once. The diagnostic readout box will remember what test mode it was in before it switched to the volt/ohmmeter function.
3. Touch the test lead to the circuit or wire to be measured, then read the results on the readout box display.
4. Once all measurements are complete, press the Volt/Ohm key twice. This will return the readout box to the test mode it was in before it switched to the volt/ohmmeter function.