Engine Controls - Tests W/codes — Hyundai Sonata II (1988-1993)

INTRODUCTION

If no faults were found while performing BASIC TESTING, proceed with self-diagnostics. If no fault codes or only pass codes are present after entering self-diagnostics, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.).

Note. All voltage tests should be performed with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless specifically stated differently in testing procedures.

HARD FAILURES

Hard failures cause malfunction light to illuminate and remain on until problem is repaired. If light comes on and remains on (light may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. If a sensor fails, ECU will use a substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, the vehicle runs, but driveability will not be optimum.

INTERMITTENT FAILURES

Intermittent failures may cause malfunction light to flicker on-and-off after intermittent fault goes away. The corresponding trouble code, WILL be retained in ECU memory.

If related fault does not reoccur within a certain time frame, related trouble code will be erased from ECU memory. Intermittent failures may be caused by sensor, connector or wiring related problems. See INTERMITTENTS in TESTS W/O CODES article.

RETRIEVING CODES

Note. Ensure battery voltage is proper before retrieving codes.

Scheme 8

Scheme 8: RETRIEVING CODES

Turn ignition switch to OFF position. Connect either a voltmeter between MPI diagnostic terminal and ground terminal of diagnostic connector, or multi-use tester (scan tool) to diagnostic connector and cigarette lighter. (Scheme 8) Turn ignition switch to ON position and disclosure of ECU memory (fault codes) will begin.
If using voltmeter to retrieve fault codes, it is important that voltage signals are accurately timed. Signals will appear in long and short pulses. Long pulses represent a numeral 10, whereas short pulses represent a numeral one. An example of fault code 15 would be one long pulse along with 5 short pulses.
If using scan tool, and malfunction indicator light comes on while various checks are being made, check self-diagnostic output.
After all checks have been made and/or trouble codes recorded, make necessary repairs. After repairs have been made, retest component(s) to ensure problem has been corrected.

Code Number	Fault Item	(2) Probable Cause	See
11	O2 Sensor	Fuel Pres., Injectors, Vacuum Leak, O2 Sensor	(Scheme 10)
12	Airflow Sensor	Airflow Sensor	(Scheme 10)
13	Intake Air Temperature Sensor	Intake Air Temperature Sensor	(Scheme 10)
14	Throttle Position Sensor	Throttle Position Sensor, Idle Switch	(Scheme 9) and (Scheme 11)
15	Motor Position Sensor	Motor Position Sensor	(Scheme 11)
21	Coolant Temperature Sensor	Coolant Temperature Sensor	(Scheme 11)
22	Crank Angle Sensor	Crank Angle Sensor	(Scheme 9) and (Scheme 12)
23	TDC Sensor (No. 1 Cylinder)	Distributor
24	Vehicle Speed Sensor Reed Switch	Vehicle Speed Sensor Reed Switch
25	Barometric Pressure Sensor	Barometric Pressure Sensor	(Scheme 12)
41	Fuel Injector	Injector Coil Resistance	(Scheme 9) and (Scheme 13)
42	Fuel Pump	Control Relay	(Scheme 9)
43	EGR Temperature Sensor (Calif. Only)	EGR Temp. Sensor, Vlv., Ctrl. Sol., Ctrl. Vac.	(Scheme 13)
(1) No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter. (2) Component, harness and connector are always a probable cause for setting a fault code.

(1)	No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter.

(2)	Component, harness and connector are always a probable cause for setting a fault code.

DIAGNOSTIC CODE - EXCEL (1)

Code Number	Fault Item	(2) Probable Cause	See
11	O2 Sensor	Fuel Pres., Injectors, Vacuum Leak, O2 Sensor	(Scheme 15)
12	Airflow Sensor	Airflow Sensor	(Scheme 15)
13	Intake Air Temperature Sensor	Intake Air Temperature Sensor	(Scheme 16)
14	Throttle Position Sensor	Throttle Position Sensor, Idle Switch	(Scheme 16)
15	Motor Position Sensor	Motor Position Sensor	(Scheme 16) and (Scheme 17)
21	Coolant Temperature Sensor	Coolant Temperature Sensor	(Scheme 17)
22	Crank Angle Sensor	Crank Angle Sensor	(Scheme 14) and (Scheme 17)
23	TDC Sensor (No. 1 Cylinder)	Distributor
24	Vehicle Speed Sensor Reed Switch	Vehicle Speed Sensor Reed Switch
25	Barometric Pressure Sensor	Barometric Pressure Sensor	(Scheme 18)
41	Fuel Injector	Injector Coil Resistance	(Scheme 15) and (Scheme 19)
42	Fuel Pump	Control Relay	(Scheme 14)
43	EGR Temperature Sensor (Calif. Only)	EGR Temp. Sensor, Vlv., Ctrl. Sol., Ctrl. Vac.	(Scheme 19)
(1) No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter. (2) Component, harness and connector are always a probable cause for setting a fault code.

(1)	No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter.

(2)	Component, harness and connector are always a probable cause for setting a fault code.

DIAGNOSTIC CODE - SONATA 2.4L (1)

Code Number	Fault Item	(2) Probable Cause	See
11	O2 Sensor	Fuel Pres., Injectors, Vacuum Leak, O2 Sensor	(Scheme 23)
12	Airflow Sensor	Airflow Sensor	(Scheme 23)
13	Intake Air Temperature Sensor	Intake Air Temperature Sensor	(Scheme 24)
14	Throttle Position Sensor	Throttle Position Sensor, Idle Switch	(Scheme 24)
21	Coolant Temperature Sensor	Coolant Temperature Sensor	(Scheme 24)
22	Crank Angle Sensor	Crank Angle Sensor	(Scheme 21) and (Scheme 25)
23	TDC Sensor (No. 1 Cylinder)	Distributor
24	Vehicle Speed Sensor Reed Switch	Vehicle Speed Sensor Reed Switch
25	Barometric Pressure Sensor	Barometric Pressure Sensor	(Scheme 25)
41	Fuel Injector	Injector Coil Resistance	(Scheme 26) and (Scheme 27)
42	Fuel Pump	Control Relay	(Scheme 21)
43	EGR Temperature Sensor (Calif. Only)	EGR Temp. Sensor, Vlv., Ctrl. Sol., Ctrl. Vac.	(Scheme 26)
(1) No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter. (2) Component, harness and connector are always a probable cause for setting a fault code.

(1)	No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECU will be indicated by a continuous voltage reading on voltmeter.

(2)	Component, harness and connector are always a probable cause for setting a fault code.

DIAGNOSTIC CODE - SONATA 3.0L (1)

CLEARING CODES

After testing and repairs are completed, disconnect negative battery cable for at least 15 seconds to clear codes.

ECU LOCATION

Application	Location
Excel	Under left side of dash.
Sonata	Passenger side kick panel.

ECU LOCATIONS

SUMMARY

If no hard fault codes (or only pass codes) are present, driveability symptoms exist or intermittent codes exist, proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e. ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.