ECI - ECI W/Intercooler Test Procedures
85mitsubishi02SUBJECT:
1985.5 STARION ECI TEST PROCEDURES
NO. STB-85-14-003
DATE May, 1985
MODEL 1985.5 Starion w/Intercooler
PURPOSE ECI test values for the 1985.5 Starion with intercooler are different from those published in the 1985 Starion Service Manual. The tables on pages 14-30 and 14-31 do not apply to models with intercooler, and the terminal connectors on the ECU are also different. Therefore, when performing an ECI voltage check on a 1985.5 Starion with intercooler, use the information in this bulletin instead of the information in the Service Manual.
TWO TEST PROCEDURES This bulletin contains two test procedures. The first allows you to check the ECI system voltages at the ECU with your digital voltmeter. The second tells how to perform the tests with the ECI Checker.
FIGURE 1:
1. VOLTMETER TEST PROCEDURE The voltmeter test procedure is particularly useful when you want to check the ECI system without unplugging the computer (and consequently erasing the ECI memory).
Voltages are measured right at the computer on the right cowl kick panel. Attach thin wire probes to your digital voltmeter. Insert the probes into the tops of the connectors on the computer as shown in Fig. 1.
You don't have to unplug the connectors, but you may find it convenient to remove the computer from the kick panel to make it easier to reach the connector terminals.
CAUTION: Short-circuiting the positive (+) probe between a connector terminal and ground could damage the vehicle wiring, the sensor, the ECU, or all three. Use care to prevent this! Insulate the exposed part of the probe with insulating material as a precaution.
VOLTMETER TEST PROCEDURE
1. Remove the trim panel below the glovebox and the right side kick panel to reach the computer terminal connectors.
2. Attach the black lead of your voltmeter to a good groundone of the computer mounting screw holes would be satisfactory. (Use a jumper to ground the computer box if you have removed it from the kick panel for this test.)
3. Refer to "1985.5 Starion Intercooler ECI System Check Procedure Chart I" on page 3. Note the connector terminal callouts in the second column. Insert the positive probe into each connector terminal in turn. Switch the ignition from "LOCK" to "ON," and compare the voltage with that shown in the chart. For example, when the probe is on terminal B1 the voltmeter should read system voltage.
4. Proceed until you have checked all the terminals in Chart I, or until a voltage is found that is out of specification. If you obtain a voltage reading out of specification, go to Step 5. If all voltages are within specification, go to Step 6.
5. When you find a voltage that is out of specification (except TPS), measure sensor voltage output at the sensor terminal of the same color wire as in the computer terminal for that sensor. This tells you whether the voltage variation is in the sensor or in connectors and wiring.
Correct any loose connections, replace sensors as required, and then disconnect the battery for 30 seconds to erase the computers memory of the malfunction. Re-check the appropriate terminal to verify that the malfunction has been corrected.
NOTE:
If the TPS voltage is out of specification, remember that the TPS produces a failure signal if the throttle is blipped when shutting down the engine. Restart the engine and then let it stop without depressing the accelerator. Measure the TPS voltage at the computer, and, if necessary, at the sensor connector.
6. Perform the checks in Chart II. If an out-ofspecification voltage is found, locate the sensor and measure its output right at the connector. If OK, then you know the wiring or connector is the source of the discrepancy.
NOTE:
If the oxygen sensor voltage is out of specification, drive the car until it is warm enough to activate the oxygen sensor and then without shutting off the engine, measure the voltage output of the oxygen sensor at the computer.
7. Correct connections and replace sensors as required, and then disconnect the battery for 30 seconds to erase the computers memory of the malfunction. Re-check the appropriate terminal to verify that the malfunction has been corrected.
NOTE:
To prevent damage to the computer, be sure the ignition switch is OFF before disconnecting the battery cable.
It is not necessary to perform the tests in any prescribed sequence. We recommend beginning with the "ignition "LOCK-ON" series and ending with the "IDLE" series, keeping in mind that some of the tests require the engine be fully warmed up. For convenience, begin with connector "A" and then go to connector "B."
II. ECI CHECKER TEST PROCEDURE Connect the ECI checker to the ECU using 1985.5 ECI harness connector MD998433. Perform the checks in "1985.5 Starion Intercooler ECI System Check Procedure Charts III and IV," Page 4. Then perform the two voltmeter checks in Chart V, Page 5.
1985.5 STARION INTERCOOLER ECI SYSTEM CHECK PROCEDURE CHART I
1985.5 STARION INTERCOOLER ECI SYSTEM CHECK PROCEDURE CHART II
1985.5 STARION INTERCOOLER ECI SYSTEM CHECK PROCEDURE CHART III
1985.5 STARION INTERCOOLER ECI SYSTEM CHECK PROCEDURE CHART IV
1985.5 STARION INTERCOOLER ECI SYSTEM CHECK PROCEDURE CHART V