Retrieving Codes

WARNING: This page is about a different car, the 1989 Hyundai Sonata. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Ensure battery voltage is proper before 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. See Fig 1 . Turn ignition switch to "ON" position and disclosure of ECU memory (fault codes) will begin.

Fig 1: Self-Diagnostic Connector Location
Courtesy of HYUNDAI MOTOR CO.
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.

DIAGNOSTIC CODE ⁽¹⁾

Code Number

Fault Item

Probable Cause ⁽²⁾

O2 Sensor

Fuel Pres., Injectors, Vacuum Leak, O2 Sensor

Airflow Sensor

Intake Air Temp Sensor

Throttle Pos Sensor

Throttle Position Sensor, Idle Switch

Motor Position Sensor

Coolant Temp Sensor

Coolant Temperature Sensor

Crank Angle Sensor

TDC Sensor (No. 1 Cyl)

Distributor

Speed Sensor Reed Swtch

Vehicle Speed Sensor Reed Switch

Barometric Pressure Sensor

Fuel Injector

Injector Coil Resistance

Fuel Pump

Control Relay

EGR Temp Sensor (Ca. Only)

EGR Temp. Sensor, Vlv., Ctrl. Sol., Ctrl. Vac.

⁽¹⁾	No fault codes in memory will be indicated by 9 short voltmeter pulses. Faulty ECM 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.