1.6 & 2.2l Feedback Carburetor System Dodge Aries I

DESCRIPTION

The Electronic Fuel Control system (EFC) is used on all 1.6L and 2.2L carbureted engines with front wheel drive. EFC is an electronically-controlled system that closely controls air/fuel ratio and ignition timing. The Spark Control Computer (SCC) is the heart of the system.

This computer provides the capability of igniting a lean air/fuel mixture according to different modes of engine operation. Also, during closed loop operation, the computer maintains the air/fuel mixture close to the ideal ratio of 14.7:1.

OVERVIEW

The EFC system consists of 6 sub-systems: fuel control, spark control, throttle control, data sensors, Spark Control Computer (SCC) and catalytic converter.

FUEL CONTROL

All models are equipped with feedback carburetors which contain an electrically-operated oxygen feedback solenoid. This solenoid meters the main fuel system of carburetor and operates in parallel with the conventional fixed main metering jets. The computer controls the operation of the solenoid in response to signals received from data sensors. (Scheme 19)

Sectional View of Carburetor With Oxygen Feedback Solenoid. Scheme 19

When the solenoid is de-energized by the computer, the solenoid valve spring pushes upward through main system fuel valve. When de-energized, the solenoid main metering orifice is fully uncovered, providing the richest mixture for any given air flow.

When the solenoid is energized by the computer, the solenoid main metering orifice is fully sealed. This solenoid position offers the leanest mixture within the carburetor for any given air flow.

The main system fuel may be regulated between richest and leanest mixture conditions by controlling the amount of time that the solenoid is energized and de-energized. The computer controls the duration of time that the solenoid is energized in comparison to total time of solenoid operation and in response to engine operating conditions and/or oxygen sensor signals. In this manner, the ideal air/fuel ratio can be constantly maintained.

SPARK CONTROL

Spark control allows the computer to determine the exact instant that ignition is required, then signals ignition coil to produce electrical impulses which fire the spark plugs. The computer eliminates the need for either vacuum advance units or centrifugal advance weights. Spark control operates in one of the following modes

Start Mode

During cranking, an electrical signal from the distributor is fed into the computer, which causes the computer to fire the spark plugs at a fixed amount of advance.

Run Mode

Once the engine starts and is operating normally, the timing will be controlled by the computer, based upon information received by the data sensors.

Spark timing and dwell cannot be adjusted in the run mode. If the computer fails, the system will go into the start mode. This enables the vehicle to be driven in for repair; but performance and fuel economy will be poor. If the start mode fails, the engine will not start or run.

The amount of spark advance is determined by engine speed and engine vacuum, based on the following conditions

1. Advance based upon engine vacuum is allowed by the computer when the carburetor switch is open. The amount of advance is programmed into the computer and is proportionate to the amount of vacuum and engine RPM.
2. Advance based upon engine speed (RPM) is allowed by the computer when the carburetor switch is open and advance from vacuum is not changing. This advance from speed is programmed into the computer, controlled by engine RPM and will build at a slow rate. If carburetor switch closes, advance from speed will be canceled.

THROTTLE CONTROL

The throttle control system is used to maintain or raise engine speed for certain conditions. The conditions when engine speed is raised are during A/C or heated rear window operation, or during timer operation. There are 2 timers used in this system. When the engine is started, one of the timers provides a 2 second delay, during which engine speed is raised. When the throttle is closed, another timer prevents the throttle from closing all the way immediately.

Hall Effect Pick-Up Assembly

This device is located in the distributor to supply a basic timing signal to the computer. From this signal, the computer can determine engine speed (RPM), when each piston is coming up on its compression stroke or when engine is in the start mode. (Scheme 20)

Location of Hall Effect Pick-up Assembly in Distributor. Scheme 20

Coolant Sensor

The sensor is located on the thermostat housing and supplies a signal to the computer when engine coolant temperature reaches a predetermined temperature.

This information is required to prevent air/fuel ratio from changing until engine reaches normal operating temperature. The computer also controls the amount of spark advance with a cold engine. (Scheme 21)

Location of Coolant Sensor The 1.6L engine is shown. Scheme 21

Vacuum Transducer

The vacuum transducer is mounted on the computer and provides the computer with a signal of the amount of engine vacuum. Engine vacuum is used by the computer to determine how much to advance or retard ignition timing and to change air/fuel mixture.

Carburetor Switch

This switch is located on the end of the idle stop to signal the computer when the engine is at idle. When the carburetor switch contacts the throttle lever ground, there will be a CANCELLATION of spark advance and idle control of the air/fuel mixture. (Scheme 22)

Location of Carburetor Switch 1.6L engine shown (2.2L is similar). Scheme 22

Oxygen Sensor

This sensor is located in the exhaust manifold to signal the computer of oxygen content of exhaust gases. The voltage output of the oxygen sensor is proportional to oxygen content of exhaust gases. The computer will adjust the air/fuel mixture (vary the time of the duty cycle solenoid) to a level which will maintain operating efficiency of the 3-way catalyst system and engine.

SPARK CONTROL COMPUTER

The computer is located on the left inner fenderwell, near the battery. The computer consists of a printed circuit board which simultaneously receives signals from all data sensors and analyzes these signals to determine correct ignition timing and air/fuel mixture. After determining spark advance, the computer will operate the engine in one of the following modes

Open Loop Mode

During cold engine operation, the air/fuel ratio is controlled by information programmed into the computer by the manufacturer. Until normal operating temperature is reached, the air/fuel mixture will be fixed at a rich level to allow proper engine warm-up. During this mode of operation, air from the AIR pump is injected "upstream" in the exhaust manifold to assist in heating up the oxygen sensor.

Closed Loop Mode

Once normal engine operating temperature is reached, the air/fuel ratio is controlled by the computer, based upon information received from the oxygen sensor.

Location of Spark Control Computer. Scheme 23

CATALYTIC CONVERTER

Proper emission control is accomplished with the special catalytic converter system used with the EFC system. All models use a front converter with air injection line.

Note. Similarities exist between external characteristics of each converter system. However, extreme care must be exercised during replacement of converters due to internal design differences.

PRELIMINARY TESTS

1. A malfunction in the EFC system may result in engine surge, hesitation, rough idle and/or poor fuel economy. Before making any tests, check all vacuum and electrical wiring for proper routing and connections, and check for exhaust and intake manifold leaks.
2. Check for spark at spark plug wire, for fuel in carburetor, for fouled spark plugs, and for improper engine timing. Using an ohmmeter, check resistance of ignition coil-to-distributor secondary wire. Resistance should be 250-600 ohms per inch (3000-7200 ohms per foot). Replace wire if not to specifications.
3. Connect ohmmeter leads to ignition coil positive and negative terminals. Coil primary resistance should be 1.6-1.8 ohms. Remove coil secondary wire and connect ohmmeter leads to coil's negative and secondary terminals. Coil secondary resistance should be 9,400-22,700 ohms. If either ohmmeter reading is not to specification, replace ignition coil.
4. If tests in steps 2 and 3 prove satisfactory, system testing may begin.

Note. The Spark Control Computer controls ignition timing as well as air/fuel mixture. Before testing EFC system, perform spark control test.

Ignition System Starting Test

1. Remove coil wire from distributor cap. Hold end of wire 1/4" away from good engine ground. Have assistant crank engine, while you watch for spark at secondary wire. Spark should be constant and bright blue.
2. If there is a good spark, continue cranking engine while slowly moving secondary wire away from ground. Look for arcing at coil tower. If arcing occurs, replace coil. If spark is weak or not constant, or if there is no spark, proceed to "Failure to Start Test".
3. If spark is good and there is no arcing at the coil tower, secondary voltage is satisfactory. Make sure it is reaching spark plugs by checking distributor rotor, cap, spark plug wires and spark plugs.
4. If all of these components check okay, ignition system is not at fault. Check fuel system or engine for mechanical damage.

Failure To Start Test

Scheme 24

Scheme 25

1. Measure and record battery voltage. Check battery specific gravity, which must be 1.220 (temperature corrected) to deliver proper voltage to ignition system.
2. Remove coil secondary wire from distributor cap and hold 1/4" from a good ground. Prepare a special jumper wire assembly. (Scheme 24) With ignition switch on, momentarily touch special jumper wire to ground and coil negative terminal. A spark should be obtained at secondary wire. (Scheme 24): Jumper Wire Assembly for Grounding Coil Negative Terminal
3. If spark was obtained, proceed to step 6. If no spark resulted, turn ignition off and disconnect 10-pin harness connector from computer. (Scheme 25) Turn ignition back on and again, using special jumper wire, connect negative terminal momentarily to ground. Spark should be obtained.
4. If spark was obtained, but engine will not start, computer output is shorted. Replace computer. If no spark resulted in step 3, connect positive lead of voltmeter to coil positive terminal and negative lead to a good ground. Reading should be within 1 volt of battery voltage. If not, check wiring between battery and coil positive terminal.
5. If correct voltage was recorded in step 4, move voltmeter positive lead to coil negative terminal. Again, voltage should be within 1 volt of battery voltage. Replace ignition coil if voltage is not present or if voltage is present, but no spark results when shorting negative coil terminal with jumper wire. (Scheme 25): Distributor and Computer Harness Connectors Used in Testing Electronic Spark Control System
6. If spark was obtained in step 2, or if in step 5 correct voltage was obtained but engine would not start, hold carburetor switch open with a thin cardboard insulator. Measure voltage between carburetor switch and ground. Reading should be within 1 volt of battery voltage. If so, proceed to step 10.
7. If battery voltage was not indicated in step 6, turn ignition off and disconnect 10-pin harness connector from computer. Turn ignition on. Connect positive lead of voltmeter to cavity No. 2 of connector and negative lead to ground. Reading should be within 1 volt of battery voltage.
8. If no battery voltage is present, check wiring from battery to ignition switch to cavity No 2. Use an ohmmeter if necessary to check continuity of wires. Correct problem and repeat step 7. If voltage was present in step 7, turn ignition off and connect ohmmeter leads to carburetor switch terminal and cavity No. 7 of 10-pin connector.
9. If no continuity is found, check for open wire between cavity No. 7 and carburetor switch. If continuity was indicated, connect ohmmeter leads to cavity No. 10 and to a good ground. If continuity exists, replace computer, as correct power is entering computer, but not leaving it. Repeat step 6. If no continuity existed between cavity No. 10 and ground, check for an open wire in the ground system.
10. Reconnect 10-pin harness connector to computer. Turn ignition on and hold secondary coil wire 1/4" from a good ground. Disconnect 3-wire distributor connector from distributor. Attach jumper wire between cavities 2 and 3 of harness connector. A good spark should jump from coil wire to ground.
11. If spark resulted, but engine will not start, replace Hall Effect Pick-Up. Before replacing, however, always be sure rotor shutter blades are grounded. Connect one ohmmeter lead to a good ground and touch other lead to shutter blade. (Scheme 20) If no continuity, push down on rotor to seat against shaft. If still no continuity, replace rotor. If shutter blade is grounded, then proceed to replace Hall Effect Pick-Up.
12. If no spark resulted in step 10, connect voltmeter positive lead to distributor harness connector cavity No. 1 and negative lead to ground. Reading should be within 1 volt of battery voltage. If no battery voltage is present, proceed to step 15. If voltage was correct, turn ignition off and disconnect 10-pin harness connector from computer.
13. Connect ohmmeter leads between cavity No. 2 (Black/Light Blue wires) of distributor harness connector and cavity No. 9 of 10-pin connector. Then connect leads to cavity No. 3 (Gray wire) of distributor harness connector and cavity No. 5 of 10-pin connector.
14. If no continuity is present, repair open wires. If continuity exists, replace computer, as power is going into computer, but not coming out. Repeat step 10.
15. If there was no battery voltage in step 12, turn ignition off, disconnect 10-pin connector and connect ohmmeter leads to cavity No. 1 of distributor harness connector and cavity No. 3 of 10-pin connector. If no continuity exists, repair wire and repeat step 10.
16. If continuity existed in step 15, turn ignition on and check for battery voltage with voltmeter positive lead in cavity No. 2 of 10-pin connector and negative lead in cavity No. 10. If battery voltage is present, but vehicle will not start, replace computer and repeat step 10. If no battery voltage is present, check ground wire and repeat step 10.

Spark Control Computer Spark Test

1. Warm engine to normal operating temperature. Set basic timing. Disconnect carburetor switch or unground it. Be sure coolant temperature sensor is connected and working properly.
2. Remove and plug vacuum hose at vacuum transducer. Connect an auxiliary vacuum supply to vacuum transducer and apply 16 in. Hg. Increase engine speed to 2000 RPM and wait 1 minute before checking specifications. Advance specifications are in addition to basic advance. See 1985 SPARK ADVANCE TEST SPECIFICATIONS table. NOTE: On some systems with an accumulator (timer), the specified time must be reached with the carburetor switch ungrounded before checking for specified spark advance.
3. If computer fails to obtain settings, replace computer.

1985 SPARK ADVANCE TEST SPECIFICATIONS (1)

ELECTRONIC THROTTLE CONTROL SYSTEM TEST

1. Connect a tachometer to engine. Warm engine to normal operating temperature. Depress accelerator, and release it. Engine speed should not immediately return to idle. On vehicles equipped with A/C or heated rear window defogger, a slight increase in idle speed should be observed while A/C or defogger are turned on.
2. Turning off either device will return idle speed to normal. As the A/C clutch cycles on and off, the throttle kicker solenoid (solekicker) plunger should extend and retract. If plunger does not move with clutch cycling, or after engine starts, or when defogger is turned on, check the kicker system for vacuum leaks. If engine speed does not increase as specified, disconnect the 6-wire connector at carburetor.
3. Connect ohmmeter leads from ground to solenoid terminal that was connected to Black wire. Resistance should be 20-100 ohms. If not, replace solenoid. Reconnect solenoid. Start vehicle and immediately (before 2 second time delay times out) measure voltage across vacuum solenoid terminals.
4. Voltage should be within 2 volts of charging system voltage. If not, replace computer. Turn on A/C or defogger after time delay has timed out. Charging voltage should once again be present at solenoid.

ELECTRONIC FUEL CONTROL SYSTEM TESTS

Note. The "Spark Control Computer Spark Test" should be made prior to beginning any test on EFC system. The following tests should be performed in the sequence given.

Preliminary Fuel Tests

1. Connect fuel pump pressure tester to fuel line at carburetor. Crank engine for 10 seconds. Fuel pump pressure should be 1-4 psi (.07-.28 kg/cm 2 ). If pressure is okay, check carburetor inlet circuit and repair as necessary.
2. If pressure was not to specifications, connect fuel pressure tester to fuel line before fuel filter. Crank engine for 5 seconds. Fuel pressure should be 1-4 psi (.07-.28 kg/cm 2 ). If pressure is now okay, replace fuel filter.
3. If pressure is still not to specifications, connect a vacuum gauge to the fuel pump inlet line. Disconnect the outlet fuel line from the fuel pump. Crank engine for 10 seconds. Vacuum gauge should read at least 10 in. Hg. If vacuum is okay, check for restricted fuel lines, improper fuel tank venting, and defective tank filter. If vacuum is not to specifications, replace fuel pump.

Carburetor Oxygen Feedback Solenoid Test (Solenoid Does Not Respond to Computer)

1. Turn ignition switch to the "RUN" position and open carburetor switch. Connect voltmeter positive lead to oxygen feedback solenoid Green wire at carburetor 6-wire connector. Connect negative lead to ground.
2. Voltmeter should pulsate and solenoid should make a clicking sound. If clicking is difficult to hear, hold a small screwdriver against the solenoid; you should feel it pulsate. If voltmeter pulsates and solenoid clicks, check for a poor connection in the circuit. If voltmeter is not pulsating but reads 0-1 volt, proceed to step 4.
3. If voltmeter does not pulsate, but reads within 1 volt of battery voltage, turn ignition switch off. Disconnect 14-pin connector. Connect voltmeter positive lead to cavity No. 12 of the 14-pin connector. Attach negative lead to ground. Turn ignition switch to "RUN". If voltmeter reads within 1 volt of battery voltage, replace computer. If voltage is otherwise, repair wire between cavity No. 12 and oxygen solenoid.
4. If in step 2, voltmeter did not pulsate, but read 0-1 volt, disconnect 14-pin connector. If voltage is now within 1 volt of battery voltage, replace the computer. If not, turn ignition switch off. Disconnect 6-wire carburetor connector. Connect ohmmeter leads to Tan and Green wires of 6-wire-connector. Ohmmeter should show resistance, the amount being unimportant. If circuit is open, replace oxygen feedback solenoid.
5. If resistance was indicated in step 4, connect voltmeter positive lead to the Blue wire of 6-wire harness connector. Connect negative lead to ground. Turn ignition switch to "RUN". Voltmeter should read within 1 volt of battery voltage.
6. If voltage is okay, check the Green wire from the oxygen feedback solenoid to the computer for a short to ground. If in step 5 no voltage was indicated, check the Blue wire to the ignition switch for an open.

Scheme 26

1. Turn the ignition switch off. Connect voltmeter positive lead to oxygen feedback solenoid Green wire in carburetor 6-wire connector. (Scheme 26) Attach negative lead to ground. Disconnect and plug vacuum hose at computer. Connect an auxiliary vacuum supply to computer, applying 14 in. Hg. Connect tachometer to engine. (Scheme 26): Carburetor 6-Wire Connector and Oxygen System Test Connector
2. Disconnect the oxygen system test connector, located on left fender shield by shock tower. Reconnect connector so that only its Green/White wire is connected. (Scheme 26)
3. On Man. Trans. models, disconnect speed sensor connector. Stick a straight pin into wire of cavity No. 5 of the computer 10-pin connector. Connect a jumper wire between the straight pin and White/ Orange wire of speed sensor harness connector.
4. On all models, start engine and run it for 1 minute. Raise engine speed to 2000 RPM. Hold oxygen system test connector's open terminal (Black wire) with one hand and touch battery positive terminal with other hand. (Scheme 26) CAUTION: Do not touch test connector terminal directly to battery positive terminal.
5. Voltmeter reading should decrease toward 0 volts. If oltage does not decrease, proceed to step 8. If voltage decreases, reconnect oxygen system test connector with engine still running at 2000 RPM. Wait for a few seconds for oxygen system to begin working. If voltage is below 7 volts, proceed to step 7.
6. If reading in step 5 was 7-14 volts, remove air cleaner cover and close down choke blade. Voltmeter reading should decrease toward 0 volts. If so, perform Carburetor Switch Test. If voltage does not decrease, check oxygen sensor wire for an open circuit to test connector. If no open is found, replace oxygen sensor.
7. If voltage was below 7 volts in step 5, disconnect hose from PCV valve and put your finger over it. Slowly remove your finger, allowing air to enter hose. Voltmeter reading should increase toward 14 volts. If voltage increases, proceed to Carburetor Switch Test. If voltage does not increase, check for a short in oxygen sensor wire leading to test connector. If none is found, replace oxygen sensor.
8. Return engine speed to idle. Turn engine off. Disconnect 14-pin connector from computer. Connect ohmmeter leads to cavity No. 10 of connector and to disconnected Black wire terminal on computer side of oxygen sensor test connector. If ohmmeter indicates continuity, replace computer. If no continuity is indicated, repair open in Black wire.

Carburetor Switch Test

1. With engine at normal operating temperature, turn ignition off and disconnect 10-pin connector from computer. With throttle completely closed, connect ohmmeter leads to cavity No. 7 and ground. Continuity should exist without resistance.
2. If no continuity is indicated, check wire from cavity No. 7 to carburetor switch terminal. If continuity is indicated with resistance, clean corrosion from carburetor switch. Also check carburetor switch for proper operation.
3. Open throttle and again check for continuity from cavity No. 7 to ground. There should be no continuity. If continuity exists, check wire from cavity No. 7 for a short to ground. If readings are not as described, replace carburetor switch.

Note. After performing carburetor switch test, perform tests on the coolant sensors, spark control system and fuel control system.

Coolant Sensor Test (1.6L)

1. Turn ignition off and disconnect wire connector from sensor. Connect one ohmmeter lead to one sensor terminal and the other lead to remaining sensor terminal.
2. Ohmmeter should indicate 382,000-22,000 ohms at -40° to 20°F (-130 to 7°C); 36,000-3,300 ohms at 50-100°F (10-38°C); and 3,900-176 ohms at 140-245°F (60-118°C). If not to specifications, replace sensor.

Scheme 27

1. Turn ignition off and disconnect wire connector from sensor. (Scheme 27) Connect one ohmmeter lead to terminal 1 of sensor (Black/Light Blue wire). Connect other ohmmeter lead to terminal 3 (Black/Red wire). Ohmmeter should read 20-200 ohms below 150°F (66°C); 100-1500 ohms at 150-200°F (66-94°C); and 400-6000 ohms above 200°F (94°C) (Scheme 27): Coolant Sensor Terminals for 2.2L Engine
2. Move ohmmeter lead from terminal 3 to terminal 2 (Black/ Orange wire). Ohmmeter should indicate 382,000-22,000 ohms at -40° to 20°F (-130 to 7°C); 36,000-3,300 ohms at 50-100°F (10-38°C); and 3,900-176 ohms at l40-245°F (60-118°C). If resistance is not to specifications, replace coolant sensor.

Scheme 28

1. Disconnect 14-pin connector from computer. Disconnect coolant sensor connector. Connect ohmmeter leads to terminal 9 of 14-pin connector and terminal 3 of sensor connector. Move ohmmeter leads to terminal 11 of 14-pin connector and terminal 2 of sensor connector. (Scheme 28): Coolant Sensor Testing Connections for 2.2L Engine
2. Continuity should exist in both instances. If not, replace or repair wiring harness as necessary.

Wiring Diagram for Chrysler 1.6L and 2.2L EFC System. Scheme 29

TEST 1 - CHECKING DIAGNOSTIC SYSTEM FOR FAULT CODES

1. Connect diagnostic readout box to engine harness connector. Put system into "Diagnostic Mode". Record all codes. NOTE: If fault codes 22, 28, 25 or 26 appear at this time, proceed to «CODE-TO-TEST IDENTIFICATION CHART»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) .
2. Turn ignition switch off and disconnect the computer 14-wire connector for one minute and then reconnect it. Start engine and run for 2 minutes. Turn engine off. Put system into "Diagnostic Mode". Record all codes.
3. If same code appears before and after engine is started, the problem still exists. Proceed to «CODE-TO-TEST IDENTIFICATION CHART»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) . If a code does not reappear after the engine is started, the problem no longer exists but was intermittent. Check for loose or corroded wiring connections in the circuit. Use wiring diagram as a guide.

CODE AND TEST IDENTIFICATION

CODE IDENTIFICATION

TEST IDENTIFICATION

CODE-TO-TEST IDENTIFICATION CHART (1)

Scheme 30

Scheme 31

Scheme 32

1. Connect diagnostic readout box connected to the engine harness connector. Carburetor switch open. Ignition switch in "RUN" position. The "Read/Hold" switch in the "Hold" position. Code 55 on the display of the readout box.
2. Connect a voltmeter to the Green oxygen solenoid wire at the carburetor 6-wire connector and ground. Press and hold the ATM button until code 91 appears on display. If voltmeter reading is pulsating and solenoid clicking, check for poor connection in harness circuit. If voltmeter is not pulsating but reads within one volt of battery voltage, go to step 4). (Scheme 30): Carburetor 6-Wire Connector
3. If voltmeter is not pulsating but reads 0-1 volt, disconnect computer 14-wire connector. If voltage is now within one volt of battery voltage, replace computer. If voltage is not within battery, go to step 6).
4. Turn ignition off. Disconnect computer 14-wire connector. Connect voltmeter to cavity No. 12 of 14-wire connector and ground. Turn ignition switch to "RUN" position. (Scheme 31): Computer 14-Wire Connector
5. Voltmeter should read within one volt of battery voltage. If voltage is okay, replace computer. If voltage is not okay, repair open wire of cavity No. 12 leading to the oxygen solenoid. NOTE: If replacing the computer, make sure the terminals in cavity No. 12 are not spread apart so that they cannot touch the computer pin.
6. Turn ignition switch off. Disconnect the carburetor 6-wire connector. Connect an ohmmeter between the Tan and Green wires of the carburetor 6-wire connector. Ohmmeter should show resistance. The amount of resistance is not important. Just make sure that there's some resistance. If there's resistance, go to step 7). If there's an open circuit, replace the oxygen solenoid. (Scheme 32): Carburetor 6-Wire Connector
7. With carburetor 6-wire connector disconnected, connect a voltmeter to the Blue wire of the harness 6-wire connector and ground. Turn the ignition switch to the "RUN" position. If voltmeter reads within one volt of battery voltage, repair the Green wire of the oxygen solenoid to the computer for a short circuit to ground. If there's zero volts, repair Blue wire for an open circuit to the ignition switch.

Carburetor 6-Wire Harness Connector. Scheme 33

Scheme 34

Scheme 35

1. Connect diagnostic readout box to engine harness connector. Place carburetor switch in open position. Ignition in "RUN" position. Place "Read/Hold" switch in "Hold" position. Connect a voltmeter to the Green wire of the dual solenoid 3-wire connector and ground. Press and hold the ATM button until test code 93 appears on display. (Scheme 34): Solenoid 3-Wire Connector & Computer 14-Wire Connector
2. If voltmeter is pulsating and clicking, check for a poor connection in the harness circuit. If voltmeter is not pulsating but reads within one volt of battery voltage, go to step 3). If voltmeter is not pulsating but reads 0-1 volt, disconnect computer 14-wire connector. If voltage is now within one volt of battery voltage, replace computer. If not, go to step 4).
3. Check canister purge solenoid control circuit. Turn ignition switch off. Disconnect computer 14-wire connector. Connect voltmeter to cavity No. 13 of 14-wire connector and ground. Turn ignition switch to the "RUN" position. If voltmeter reads within one volt of battery voltage, replace computer. If voltage is not okay, repair wire of cavity No. 13 for an open circuit to canister purge control solenoid. (Scheme 35): Solenoid 3-Wire Connector
4. Turn ignition switch off. Disconnect dual solenoid 3-wire connector. Connect ohmmeter between Blue and Green wires of dual solenoid 3-wire connector. If ohmmeter shows any resistance, repair Green wire to computer for a short circuit to ground. If circuit is open, replace canister purge solenoid.

Scheme 36

Scheme 37

1. Connect diagnostic readout box to engine harness connector. Place carburetor switch to open position. Turn ignition switch to the "RUN" position. Place "Read/Hold" switch in the "Hold" position. Code 55 should be on the display of the readout box. (Scheme 36): Solenoid 3-Wire Connector & Computer 14-Wire Connector
2. Connect voltmeter to the Gray wire of the dual solenoid 3-wire connector and ground. Press and hold the ATM button until test code 97 appears on the display. If voltmeter reading is pulsating and the solenoid clicking, check for a poor connection in harness circuit. If voltmeter is not pulsating but reads within one volt of battery voltage, go to step 3). If voltmeter is not pulsating but reads 0-1 volt, disconnect the computer 14-wire connector. If voltage is now within one volt of battery voltage, replace computer. If not, go to step 4).
3. Check throttle control solenoid circuit. Turn ignition switch off. Disconnect computer 14-wire connector. Connect a voltmeter to cavity No. 6 of 14-wire connector and ground. Turn ignition witch to the "RUN" position. If voltmeter reads within one volt of battery voltage, voltage is okay. Replace computer. If voltage is not okay, repair wire of cavity No. 6 for an open circuit to throttle control vacuum solenoid. (Scheme 37): Solenoid 3-Wire Connector
4. Turn ignition switch off. Disconnect dual solenoid 3-wire connector. Connect ohmmeter between Blue and Gray wires dual solenoid connector. If ohmmeter shows any resistance, check Gray wire to computer for a short to ground. If circuit is open, replace throttle control solenoid.

Scheme 38

Scheme 39

1. Connect diagnostic readout box to the engine harness connector. Place carburetor switch in the open position. Turn ignition switch to the "RUN" position. Place "Read/Hold" switch in the "Hold" position. Code 55 should appear on display of readout box.
2. Connect voltmeter to the Black wire of the carburetor 6-wire connector and ground. Press and hold the ATM button until test code 98 appears on the display. If voltmeter reading is pulsating and the solenoid is clicking, check for a poor connection in the harness circuit. (Scheme 38): Carburetor 6-Wire Connector
3. If voltmeter is not pulsating buts reads within one volt of battery voltage, go to step 4). If voltmeter is not pulsating but reads 0-1 volt, disconnect the computer 14-wire connector. If voltage is now within one volt of battery, replace computer. If not, go to step 5).
4. Check V.O.S. control solenoid control circuit. Turn ignition switch off. Disconnect computer 14-wire connector. Connect voltmeter to cavity No. 8 of the 14-wire connector and ground. Turn ignition to the "RUN" position. If voltmeter reads within one volt of battery voltage, replace computer. If voltage is not okay, repair wire of cavity No. 8 for an open circuit to the V.O.S. control solenoid. (Scheme 39): Computer 14-Wire Connector & Carburetor 6-Wire Harness Connector
5. With carburetor 6-wire connector disconnected, connect a voltmeter to the Blue wire of the harness 6-wire connector and ground. Turn ignition switch to the "RUN" position. If voltmeter reads within one volt of battery voltage, repair the Black and White tracer wire of the V.O.S. solenoid to the computer for a short circuit to ground. If 0 volts, check Blue wire for an open circuit to the ignition switch.

Scheme 40

Scheme 41

1. Turn ignition switch off. Connect a voltmeter to the Green oxygen solenoid wire at the carburetor 6-wire connector and ground. Disconnect and plug vacuum hose at the computer. Connect an auxiliary vacuum supply to the computer and apply 14 in. Hg vacuum. (Scheme 40): Carburetor 6-Wire Connector & Computer 10-Wire Connector
2. Connect a tachometer to the engine. Disconnect the oxygen system test connector and then reconnect Green with White tracer wire only. If equipped with a manual transmission, disconnect the speed sensor connector. Stick a straight pin into wire of cavity No. 5 of the computer 10-wire connector.
3. Connect a jumper wire between the straight pin and the White with Orange tracer wire of the speed sensor harness connector. Start engine and wait one minute. Raise engine speed to 2000 RPM. Hold oxygen system test connector (open terminal) with one hand and touch the battery positive terminal with the other hand. If voltmeter reading decreases to 0 volts, go to step 4). If voltage does not decrease, go to step 6). (Scheme 41): O2 Test Connector
4. Check oxygen sensor. With voltmeter connected to oxygen solenoid Green wire, disconnect hose at computer and plug. Apply 14 in. Hg of vacuum to computer. Connect tachometer to engine and run engine to 2000 RPM.
5. Reconnect oxygen test connector. Wait a few seconds for oxygen system to start working. If voltmeter reading pulsates between 7 and 14 volts, go to step 6). If voltage is below 7 volts, go to step 7).
6. Check oxygen feedback system for a rich condition. Connect voltmeter to oxygen solenoid Green wire. Disconnect hose at computer and plug. Apply 14 in. Hg of vacuum to computer. Connect tachometer to engine and run engine to 2000 RPM. Disconnect oxygen test connector. If voltmeter reading decreases to 0 volt, oxygen system is okay. If voltage does not decrease, check oxygen sensor wire for an open circuit to test connector. Repair system as necessary. If there's no open circuit, replace oxygen sensor.
7. Run engine at 2000 RPM with 14 in. Hg of vacuum applied to computer. Disconnect hose from PCV valve and cover orifice. Allow air to slowly enter orifice. If voltmeter reading should increase toward 14 volts, oxygen system is okay. If voltage does not increase, check the oxygen sensor wire for a short circuit to the test connector. If there's an open circuit, repair system. If there's no short circuit, replace oxygen sensor.
8. Check oxygen feedback system for a lean condition. Connect Green with White tracer wire and disconnect oxygen system test connector. Let engine return to idle speed and then turn off engine. Disconnect computer 14-wire connector. Connect an ohmmeter between test connector (Black wire) on computer side and cavity No. 10 of the 14-wire connector. If ohmmeter shows continuity, replace computer. If there's no continuity, repair open wire to test connector.

Computer 14-Wire Connector & O2 Test Connector. Scheme 42

Scheme 43

Scheme 44

1. Disconnect coolant sensor connector. Connect one lead of an ohmmeter to terminal No. 1 of the coolant sensor. Connect other lead of ohmmeter to terminal No. 2 and then terminal No. 3 of the coolant sensor. If there's some resistance at both terminals, go to step 2). If there's resistance at one terminal and not at the other, replace the coolant sensor. (Scheme 43): Coolant Sensor Terminals, Computer 14-Wire Connector & Engine Coolant Sensor Connector
2. Make sure sensor connector is disconnected. Disconnect computer 14-wire connector. Connect an ohmmeter between cavity No. 9 of 14-wire connector and terminal No. 3 of coolant sensor connector. If ohmmeter shows continuity, go to step 3). If there's no continuity, repair wire for open circuit. (Scheme 44): Computer 14-Wire Connector & Engine Coolant Sensor Connector
3. Disconnect computer 14-wire connector and coolant sensor connector disconnected. Connect ohmmeter between cavity No. 11 of 14-wire connector and terminal No. 2 of coolant sensor connector. If ohmmeter shows continuity, replace computer. If there's no continuity, repair wire for open circuit.

Scheme 45

1. Turn ignition switch off. Remove speed sensor from transmission. Disconnect speed sensor connector. Connect ohmmeter between terminals for the speed sensor connector. Slowly rotate speed sensor one turn. Ohmmeter should show approximately 8 pulses for every turn of the speed sensor. If ohmmeter reading is okay, go to step 2). If ohmmeter reading is not okay, replace the speed sensor.
2. Check the speed sensor circuit. Disconnect speed sensor connector. Connect the positive lead of a voltmeter to the White wire with a orange tracer of the speed sensor connector. Connect the negative lead of the voltmeter to the Black with Blue tracer wire of the speed sensor harness connector. Turn ignition to "RUN" position. (Scheme 45): Speed Sensor Harness Connector
3. Voltmeter should read at least 8.5 volts. If voltage is okay, inspect transaxle drive gear to speed sensor drive gear for proper contact. If 0 volts, move voltmeter negative lead to a good engine ground. If voltmeter now reads correct voltage, repair ground wire for an open circuit. If voltmeter still reads 0, go to step 4).
4. Check speed sensor wire to computer. Turn ignition switch off. Disconnect the computer 14-wire connector. Connect an ohmmeter between cavity No. 2 of the 14-wire connector and the White with Orange tracer wire of the speed sensor harness connector. If ohmmeter shows continuity, replace computer. If no continuity, repair wire for an open circuit.

Computer 14-Wire Connector & Speed Sensor Harness Connector. Scheme 46

Scheme 47

Scheme 48

1. Disconnect diagnostic readout box from engine harness connector. Connect a voltmeter to cavity No. 4 of the engine harness connector and ground. Turn ignition switch to the "RUN" position. If voltmeter reads between 4 and 5 volts, voltage is okay. Go to step 2). If voltage is not okay, go to step 3). (Scheme 47): Diagnostic Connector
2. Turn ignition switch off. Disconnect 14-wire connector from computer. Connect ohmmeter between cavity No. 2 of engine harness diagnostic connector and cavity No. 14 of the computer 14-wire connector. If ohmmeter shows continuity, replace computer. If there's no continuity, repair wire of cavity No. 14 for an open circuit to the engine harness connector. (Scheme 48): Computer 14-Wire Connector, Diagnostic Connectors & Power Module 12-Wire Connector
3. Disconnect diagnostic readout box. Turn ignition switch off. Disconnect the 14-wire connector from the computer. Connect an ohmmeter between cavity No. 4 of the engine harness connector and cavity No. 1 of the computer 14-wire connector. If ohmmeter shows continuity, replace computer. If there's no continuity, repair wire of cavity No. 1 for an open circuit to the engine harness.

TEST 10

Note. The following test to start with a cold engine.

Scheme 49

Scheme 50

Scheme 51

Scheme 52

Scheme 53

1. Check choke and fast idle cam linkage. Set accelerator linkage to the proper start position. Remove air cleaner. Check choke plate and fast idle cam position. (Scheme 49): Choke Valve Closed
2. Choke plate should be in fully closed position and fast idle screw should be on the highest step of the fast idle cam. If choke and cam position are okay, go to step 3). Choke not fully closed or cam not in position, check for choke plate sticking or binding. Repair choke and linkage as required.
3. Check choke vacuum kick. Remove air cleaner. Set fast idle speed screw on the highest step of the fast idle cam. Remove vacuum hose from choke diaphragm. Connect an auxiliary vacuum supply to choke diaphragm. Apply 15 in. Hg of vacuum. Measure clearance between top of choke plate and air horn wall. (Scheme 50): Choke Diaphragm
4. Vacuum should hold at applied setting and choke plate should be in proper position of vacuum kick specifications. If vacuum holds and choke vacuum kick is within specifications, go to step 5). If vacuum does not hold, replace choke vacuum kick diaphragm.
5. Check heated air intake system. Disconnect air duct from air cleaner snorkel. Disconnect vacuum supply hose to heated air intake system air temperature sensor. Apply 15 in. Hg of vacuum. (Scheme 51): Heated Air Intake System
6. Vacuum should close heated air door when air temperature is below 76°F (25°C) and then slowly bleed down opening the heated air door. The 1.6L models have a vacuum delay valve at the heated air door vacuum diaphragm. This will delay the opening of the door when vacuum bleeds off.
7. If vacuum builds up and closes the heated air door and then bleeds down, go to step 8) for 1.6L models and step 9 for 2.2L models. If vacuum builds up but heated air door does not close, repair or replace door as necessary. If vacuum does not build up or does not bleed down, replace air temperature sensor. If vacuum builds up, bleeds down, but heated air door does not open, repair or replace door as required.
8. Check coolant temperature sensor (1.6L Models only). For 2.2L models, go to step 9). Disconnect coolant sensor connector. Connect ohmmeter between coolant sensor terminals. Ohmmeter should read as follows: From -40 to 20°F (-60 to -6.7°C), 382,000-22,000 ohms. From 50 to 100°F (10 to 38°C), 36,000-3,300 ohms. From 140 to 245°F (60 to 118°C), 3,900-176 ohms. If resistance is okay, go to step 11). If resistance is not okay, replace coolant sensor.
9. Check coolant temperature sensor, (2.2L models only). Disconnect coolant sensor. Connect an ohmmeter between terminals 1 and 3 of the coolant sensor. Ohmmeter should read as follows: Below 150°F (66°C), 20-200 ohms. From 150 to 200°F (66 to 93°C), 100-150 ohms. Above 200°F (93°C), 400-6,000 ohms. If resistance is okay, go to step 10). If resistance is not okay, replace coolant sensor. (Scheme 52): Coolant Sensor Terminals
10. With coolant sensor connector disconnected and ohmmeter connected between terminals 1 and 2 of 2.2L coolant sensor. Ohmmeter should read as follows: From -40 to 20°F (-60 to -6.7°C), 382,000-22,000 ohms. From 50 to 100°F (10 to 38°C), 36,000-3,300 ohms. From 140 to 245°F (60 to 118°C), 3,900-176 ohms. If resistance is okay, go to step 11). If resistance is not okay, replace coolant sensor.
11. Check EGR system CVSCC valve. Disconnect CVSCC valve at vacuum hose connector. Connect auxiliary vacuum supply to valve. Apply at least 10 in. Hg of vacuum. Vacuum should hold engine coolant temperature below 125°F (52°C). If vacuum is okay, go to step 12). If vacuum does not hold, replace CVSCC valve. (Scheme 53): EGR System CVSCC Valve
12. Check choke position with engine running. Remove air cleaner. Start engine. Check position of choke plate. Choke plate should open from a fully closed position. If choke plate is in proper position, system is okay. If choke plate is not in proper position, adjust choke as required.

TEST 11

Note. The following test begins with a warm engine.

1. Check carburetor switch. Disconnect computer 10-wire connector. Connect an ohmmeter between cavity No. 7 of 10-wire connector and ground. Open and close throttle while looking at ohmmeter.
2. Ohmmeter should show continuity with no resistance when throttle is closed and no continuity when throttle is open. If continuity is okay for 1.6L models, go to step 4); if okay for 2.2L models, go to step 5).
3. If there's no continuity with the throttle closed, repair wire of cavity No. 7 for open circuit to carburetor switch. If there is continuity with resistance when throttle is closed, clean corrosion from carburetor switch. If there's continuity with throttle open, repair wire of cavity No. 7 for a short to ground.
4. Check coolant sensor calibration, (1.6L models only). For 2.2L models, see step 5). Disconnect connector for coolant sensor. Connect ohmmeter between terminals of coolant sensor. Ohmmeter should read between 176-3,900 ohms of resistance. If resistance is okay, go to «TEST 12»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) . If resistance is not okay, replace coolant sensor.
5. Check coolant sensor calibration, (2.2L models only). Disconnect connector for coolant sensor. Connect ohmmeter between terminals 1 and 3 of coolant sensor. Ohmmeter should read 400-6,000 ohms. If resistance is okay, go to «TEST 12»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) . If resistance is not okay, replace coolant sensor.

Scheme 54

1. Remove air cleaner and start engine. Check position of choke. Choke should be fully open. If choke position is okay, go to step 3). If choke position is not okay, go to step 2).
2. Check voltage supply to choke control. With engine running, connect voltmeter to choke feed wire and ground. Voltmeter should read within one volt of battery voltage. If voltage is okay, check for binding linkage, If okay, replace choke thermostat housing. If voltage is not okay, go to step 3).
3. Check voltage supply to oil pressure switch. Turn off engine. Disconnect oil pressure switch connector. Connect voltmeter to terminal C of oil pressure switch connector and ground. Turn ignition switch to "Run" position. Voltage should be within one volt of battery voltage. If voltage is okay, go to step 4). If voltage is not okay, repair open circuit in harness to ignition switch. (Scheme 54): Engine Harness Connector
4. Check wire to choke control. Oil pressure switch connector disconnected. Connect ohmmeter between terminal A of oil pressure switch connector and choke connector. Ohmmeter should show continuity of 0 resistance. If there's continuity, replace oil pressure switch. If there's no continuity, repair open circuit in harness.

Engine Harness Connector. Scheme 55

TEST 13 - CHECKING CARBURETOR IDLE SYSTEM

1. Connect tachometer to engine. Remove air cleaner. If equipped, disconnect and plug vacuum hose at solenoid kicker. Start engine, momentarily raise engine speed above 1100 RPM, and then wait 2 minutes for idle speed to stabilize. Plug idle air bleed hole.
2. Engine speed should drop. If engine speed drops, go to step 3). If engine speed does not drop or increases, repair carburetor for a plugged circuit.
3. Connect tachometer to engine. Disconnect vacuum hose from EGR valve. Connect auxiliary vacuum supply to EGR valve. If equipped, disconnect and plug vacuum hose at solenoid kicker. Start engine, momentarily raise engine speed above 1100 RPM and then wait 2 minutes for idle speed to stabilize. Very slowly apply vacuum to EGR valve.
4. Engine speed should begin to drop when applied vacuum reaches 2 to 5 in. Hg of vacuum and continue to drop as more vacuum is applied. Engine may stall before 5 in. Hg of vacuum is applied. If engine speed drop is okay, go to step 5). If engine speed does not drop or engine speed does not drop until 5 in. Hg or more vacuum, replace EGR valve.
5. Connect tachometer to engine. Where applicable, vacuum hose at solenoid kicker plugged. Engine running at idle for than 2 minutes. Disconnect EGR hose. Connect vacuum gauge to EGR vacuum hose. Slowly increase engine speed.
6. As engine speed increases so should the reading on vacuum gauge. If vacuum reading is okay, go to «TEST 14»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system__test-14-checking-air-switching) . If vacuum is not okay, go to step 7).
7. Turn engine off. Remove connector from EGR CVSCC valve. Connect vacuum pump to either port of valve. Try to apply vacuum. Vacuum should not hold with engine coolant above 125°F (52°C). If vacuum does not hold, check EGR signal hose from carburetor, for leaks or restrictions. If vacuum holds, replace EGR CVSCC valve.

TEST 14 - CHECKING AIR SWITCHING SYSTEM

1. Remove air cleaner. Disconnect the downstream air hose from the switch/relief valve. Start engine. With engine coolant above 150°F (67°C), air should be coming from downstream air port of the switch/relief valve.
2. On 1.6L models, if air is coming from downstream air port, go to «TEST 16»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system__test-16-checking-carburetor-bowl) . On 2.2L models, if air is coming from downstream air port, go to «TEST 15»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) . On all models, if air in not coming from downstream air port, go to step 3).
3. Check air switching CVSCC valve. With air cleaner removed and engine running, disconnect vacuum hose from air switch/relief valve. Connect a vacuum gauge to hose. Vacuum should read 0 vacuum. If vacuum is okay, replace air switch/relief valve. If vacuum is present, replace CVSCC valve.

Scheme 56

1. Remove air cleaner cover. Turn ignition key to the "RUN" position while looking at solenoid plunger. Slowly open throttle. The plunger should move out when key is turned on or when throttle is opened. If plunger movement is okay, go to «TEST 17»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system). If plunger movement is not okay, go to step 2). (Scheme 56): Solenoid Plunger
2. Connect voltmeter to solenoid Red wire at carburetor 6-way connector. Turn ignition key to "RUN" position. Voltmeter should read within one volt of battery voltage. If voltage is okay, replace solenoid. If voltage is not okay, repair harness to ignition switch open circuit. NOTE: Before replacing solenoid, make sure solenoid adjusting screw is not turned in all the way preventing plunger movement.
3. Disconnect vacuum hose from solenoid kicker. Connect an auxiliary vacuum supply to solenoid kicker. Apply 15 in. Hg of vacuum and then release vacuum. The plunger should move out when vacuum is applied and return when vacuum is released. If plunger movement is okay, go to «TEST 16»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system__test-16-checking-carburetor-bowl). If plunger movement is not okay, replace solenoid kicker.

Carburetor 6-Wire Connector. Scheme 57

TEST 16 - CHECKING CARBURETOR BOWL VENT SYSTEM

1. Remove bowl vent hose from carburetor and canister. Blow lightly into hose. Air should pass through. If air passes through, go to step 2). If air does not pass through, clear hose or replace bowl vent valve. Look for liquid in hose near canister. If liquid is found, check routing of hose.
2. With bowl vent hose removed from carburetor and canister, start engine and blow lightly into hose. Air should not pass through hose. If air passed through hose, check air pressure in hose from air switch relief valve. Repair as required. If okay, replace bowl vent valve.
3. If air does not pass through, disconnect air duct from air cleaner snorkel. Disconnect vacuum supply hose to heated air intake system air temperature sensor. Apply 15 in. Hg vacuum. Vacuum should not hold and heated air door should be open. If okay, proceed to Test 17. If vacuum holds, replace sensor. If heated air door is not open, repair or replace as required.

Checking Procedure

Connect diagnostic readout box to the engine harness connector. Put the system in the ATM test mode. Press and hold the ATM button until test codes appear as follows: 1.6L and 2.2L models with oxygen feedback system, test code 92. 2.2L models without the oxygen feedback and with man. trans., test code 92. 2.2L models without the oxygen feedback system and with auto. trans., test code 93.

Test Code 91

Should hear oxygen solenoid clicking. If oxygen solenoid is clicking, press and hold ATM button until the next test code appears. If oxygen solenoid does not click, replace unit.

Test Code 92 (Manual Trans. Only)

Shift indicator light (SIL) should be blinking on instrument panel. If SIL light is blinking, go to TEST 20 , Checking Ignition Spark Advance. Press and hold the ATM button until next test code appears. If SIL light does not blink, repair circuit as necessary.

Test Code 93

The canister purge solenoid should be clicking. If canister purge solenoid is clicking, press and hold ATM button until next test code appears. If canister purge solenoid does not click, replace unit.

Test Code 96

The radiator fan should be turning on and off. If radiator fan is turning on and off, press and hold the ATM button until next test code appears. If fan does not turn on and off, is relay clicking? If relay is clicking, repair circuit fan motor as required. If relay does not click, go to TEST 18 .

Test Code 97

The electronic throttle control solenoid should be clicking. If electronic throttle control solenoid is clicking, press and hold the ATM button until next test code appears. If electronic throttle control solenoid does not click, replace unit.

Test Code 98

The VOS control solenoid should be clicking. If VOS control solenoid is clicking, turn ignition switch off and go to TEST 18 . If VOS control solenoid does not click, replace unit.

Scheme 58

1. Connect diagnostic readout box to engine harness connector. With carburetor switch open, turn ignition switch to "RUN" position. Place "Read/Hold" switch in the "Hold" position. Code 55 should be displayed on readout box. Connect voltmeter to terminal No. 2 of radiator fan relay and ground. Press and hold the ATM button until test code 96 appears on display.
2. Voltmeter reading should be pulsating and relay should be clicking. If voltmeter pulsates and relay clicks, check for poor connection in the circuit. If voltmeter is not pulsating but reads within one volt of battery voltage, go to step 3). If voltmeter is not pulsating but reads 0-1 volt, disconnect computer 10-wire connector. If voltage is now within one volt of battery voltage, replace the computer. If not within one volt, go to step 5).
3. Turn ignition switch off. Disconnect the computer 10-wire connector. Connect a voltmeter to cavity No. 8 of the 10-wire connector and ground. Turn ignition switch to the "RUN" position.
4. Voltmeter should read within one volt of battery voltage. If voltage is okay, replace computer. If voltage is not okay, repair wire of cavity No. 8 for an open circuit to radiator fan relay.
5. Turn ignition switch off. Disconnect the smaller of the two 3-wire connectors from the radiator fan relay. Connect an ohmmeter between terminals No. 1 and 2 of the radiator fan relay. Ohmmeter should show resistance. (Scheme 58): Radiator Fan Relay Terminals
6. If there's resistance, turn the ignition switch to the "RUN" position. Check for battery voltage at wire that connects to terminal No. 1 of relay. If there's voltage, repair wire of cavity No. 8 of the computer 10-wire connector for a short to ground. If there's no voltage, repair wire for open circuit to fuse No. 2. If there's an open circuit, replace radiator fan relay.

Scheme 59

1. Remove air cleaner cover. Look at plunger of solenoid kicker diaphragm while starting engine. The vacuum diaphragm plunger should move out and hold the throttle open for at least 5 minutes. It should then return the throttle to curb idle position. NOTE: Some systems may hold throttle open for less than 5 minutes.
2. If the plunger movement is okay, go to step 3). If there's no plunger movement, go to step 4).
3. Press A/C button and look at plunger for solenoid kicker vacuum diaphragm. Vacuum plunger should move out and hold the throttle open while the A/C compressor clutch is engaged. If plunger movement is okay, go to «TEST 20»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system). If there's no plunger movement, go to step 4). (Scheme 59): Solenoid Kicker Vacuum Diaphragm
4. Connect diagnostic readout box to the engine harness connector. Put system in the "Switch Test Mode". Make sure A/C control is in the "OFF" position. Press the A/C button on and off.
5. Code 88 should appear on the display when the A/C button is pressed on and then return to 00 when turned off. If code 88 appears when A/C button is turned on, replace the computer. If code 88 does not appear, go to step 6).
6. Turn ignition switch off. Disconnect computer 14-wire connector. Connect a voltmeter to cavity No. 7 of the 14-wire connector and ground. Make sure A/C button is off. Turn the ignition switch to the "RUN" position.
7. Voltmeter should read within one volt of battery voltage. If voltage is okay, replace the computer. If voltage is not okay, repair wire of cavity No. 7 for an open circuit to the A/C push button switch.
8. Turn the engine off. Disconnect the vacuum supply hose from the solenoid kicker and connect a vacuum gauge to it. Start the engine. Vacuum gauge should indicate intake manifold vacuum. If vacuum is okay, replace the computer. If there's no vacuum, repair vacuum supply from the carburetor.

Checking Secondary Ignition System

Connect engine analyzer to engine. Start engine and let engine speed stabilize for 2 minutes. Follow equipment manufacturer's procedure for secondary ignition testing and pattern analysis. If secondary ignition system is okay, go to next test. If secondary ignition is not to specifications, repair as required.

1. Connect a tachometer and timing light to engine. Ground carburetor switch. Start engine and let run until operating temperature is reached. Momentarily raise the engine speed above 1100 RPM. If equipped, disconnect and plug vacuum hose at solenoid kicker. Disconnect and plug vacuum hose at computer (engine RPM will drop when hose is disconnected).
2. Engine idle speed should be below curb idle specifications. If necessary turn idle screw to lower the engine RPM. Basic timing should be within 2° of specifications shown on emissions label. If basic timing is okay, go to step 3). If basic timing is not okay, adjust as necessary.
3. Connect tachometer and timing light to engine. Plug hose computer and solenoid kicker. Engine running at operating temperature. Remove jumper wire from carburetor ground switch. Connect auxiliary vacuum supply to computer. Apply 16 in. Hg vacuum to system. Raise engine speed to 2000 RPM. Timing should be within 4° of specification. If spark is okay, go to next test. If spark is not okay, replace computer.
4. Engine running at normal operating temperature. Return engine to idle speed.Unplug hose to computer and connect a vacuum gauge. Gauge should read manifold vacuum. If vacuum is okay, go to «TEST 21»(/dodge/aries/i-1981-1989/remont/testing-diagnostics/#16-22l-feedback-carburetor-system) . If vacuum is not okay, check vacuum supply from carburetor.

Checking Engine Idle RPM

1. Turn off all lights and accessories. Connect tachometer to engine. Disconnect and plug vacuum connector at EGR CVSCC valve. Jumper radiator fan connector so fan will run continuously. If equipped, disconnect oxygen system test connector. Remove PCV valve and allow it to draw outside air. Ground carburetor switch. If equipped, disconnect and plug vacuum hose at solenoid kicker.
2. Start engine and momentarily raise engine speed above 1100 RPM and wait 2 minutes for engine speed to stabilize. Tachometer should indicate same RPM as shown on emission label.
3. If idle speed is okay, go to next test. If idle speed is not okay, turn idle speed screw until engine RPM is the same as shown on emission label.

Checking Idle Mixture

1. Remove hose to heated air sensor from 3-wire connector and install propane supply hose in its place. Open propane main valve. Meter propane unit maximum RPM is reached.
2. Engine speed should increase by the following amounts: For 1.6L, 225 RPM; for 2.2L, 90 RPM. If engine speed is okay, go to next test. If engine speed increase in not okay, adjust according to propane assisted idle set procedure.

Checking Fast Idle RPM

1. All lights and accessories off. Tachometer connected to engine. Vacuum connector at EGR CVSCC removed and plugged. Radiator fan running. PCV valve removed. Carburetor switch grounded. Where applicable, oxygen system test connector disconnected. Engine running at normal operating temperature.
2. Turn propane valve off. Open throttle and set fast idle adjustment screws on the slowest speed step of the fast idle cam. Fast idle speed should be within specifications as shown on emission label. If fast idle speed is okay, go to next test. If fast idle speed is not okay, adjust to specifications.

Checking Throttle Stop RPM

1. All lights and accessories off. Connect tachometer to engine. Ground carburetor switch. Engine running normal operating temperature. Reconnect vacuum connector at EGR CVSCC valve. Reinstall PCV valve. Remove jumper wire from radiator fan and reconnect connector.
2. Remove power feed wire to SIS or solenoid kicker from carburetor 6-wire connector. Tachometer should read 600 RPM or less. If so, testing is completed. If engine speed is greater than 600 RPM, adjust to specifications. Testing is completed.

See also:
• CODE-TO-TEST IDENTIFICATION CHART
• TEST 10
• TEST 14
• TEST 16