Code Identification

CODE IDENTIFICATION

Code No.

System Affected

Probable Cause

12 & 13

RPM Signal

Distributor/Integrated Ignition Assembly Or Circuit, Starter Circuit, ECU

Ignition Signal

Ignitor Or Circuit To ECU, ECU

O2 Sensor Signal

O2 Sensor Or Ckt, ⁽¹⁾ O2 Sensor Heater, ECU

Coolant Temp. Sensor Signal

Coolant Temp. Sensor Or Ckt, ECU

24 ⁽²⁾

Intake Air Temp. Sensor Signal

Intake Air Temp. Sensor Or Ckt, ECU

Lean Air/Fuel Mixture

ECU, Injector Or Ckt, O2 Sensor Or Ckt, Fuel Pressure, Ignition System, Coolant Temp. Sensor, ⁽³⁾ Airflow Meter/Vacuum Sensor

Rich Air/Fuel Mixture

Fuel Pressure, ⁽³⁾ Airflow Meter/Vacuum Sensor, ECU, Injector Or Ckt, O2 Sensor Or Ckt, Cold Start Injector Or Ckt, Coolant Temp. Sensor

27 ⁽⁴⁾

Sub-O2 Sensor Signal

Sub-O2 Sensor Or Ckt, ECU

⁽³⁾ Airflow Meter/Vacuum Sensor Signal

Airflow Meter/Vacuum Sensor Or Ckt, ECU

41 ⁽²⁾

Throttle Position Sensor Signal

Throttle Position Sensor Or Ckt, ECU

42 ⁽⁵⁾

Vehicle Speed Sensor Signal

Vehicle Speed Sensor Or Ckt, ECU

43 ⁽⁵⁾

Starter Signal

Starter Signal Ckt, Ignition Switch Or Ckt, ECU

51 ⁽⁵⁾

Switch Condition Signal

A/C Switch Ckt, ECU, Neutral/Start Switch Or Ckt, TPS Or Ckt

52 ⁽¹⁾

Knock Sensor Signal

Knock Sensor Or Ckt, ECU

53 ⁽¹⁾

Knock Sensor Control (ECU)

ECU

71 ⁽⁶⁾

EGR System Malfunction

EGR System, EGR Temp. Sensor Or Ckt, ECU, EGR VSV

⁽¹⁾	Used on 4A-GE only.

⁽²⁾	CHECK ENGINE light comes on when code sets (Calif. only).

⁽³⁾	Airflow meter used on 4A-GE and vacuum sensor on 4A-FE.

⁽⁴⁾	Used on 4A-GE (Calif. only).

⁽⁵⁾	CHECK ENGINE light will not come on when code is set.

⁽⁶⁾	Used on Calif. only.