Alfa Romeo: Diagnostic Trouble Codes
Spider (Motronic ML4.1)
To access DTCs, with engine running, depress auto diagnostic push button located under rear seat. DTCs of four digits are indicated by the Check Engine lamp in a series of flashes and pauses.
Motronic ML4.1 auto diagnostic push button location. Spider models
164 (Motronic ML4.1)
To access DTCs, turn ignition On, depress auto diagnostic push button (T4), located on the lower LH side of the instrument panel, for approximately 2 1/2 to five seconds. DTCs of four digits are indicated by the Check Engine lamp in a series of flashes and pauses.
Motronic ML4.1 auto diagnostic push button location. 164 models
Diagnostic Trouble Code Interpretation
The Check Engine lamp will display DTCs by flashing frequencies and 2 1/2 second pauses. As an example, one flash, followed by a 2 1/2 second pause, followed by two flashes and another 2 1/2 second pause, followed by four flashes and a 2 1/2 second pause, followed by three flashes and another 2 1/2 second pause, indicates a DTC 1243. The DTC will be repeated until the auto diagnostic push button is depressed to proceed to the next DTC.
Clearing Diagnostic Trouble Codes
After performing all necessary repairs, the DTCs should be cleared from the ECU memory by depressing the auto diagnostic push button for more than 10 seconds, or by disconnecting and isolating the battery ground cable for approximately 10 seconds.
Battery Voltage Improper
Idle Throttle Switch Or Circuit
Full Throttle Switch Or Circuit
Engine Temperature Sensor
AFM Or Circuit
Idle Adjustment Actuator Or Circuit
HO2S Regulator Inner Adjuster Reaches Minimum Or Maximum Value Of Correction
Air Temperature Sensor
Fuel Pump Relay Or Circuit
Purge Control Solenoid Or Circuit
Output Stage Of ECU For Variable Valve Timing
Output Stage Of ECU For Check Engine Lamp
No Recognized Malfunction