Alfa Romeo 1992-1998 OBD 1 DIY (NO OBD SCANNER) Diagnostic Guide
General information
- Engine control module (ECM) incorporates self-diagnosis function.
- Malfunction indicator lamp (MIL) will illuminate if certain faults are recorded.
- ECM operates in emergency mode if sensors fail, to enable the car to be driven to the workshop.
- Trouble codes can be accessed with suitable test lamp Fig. 1.
Accessing trouble codes
- Ensure ignition switched OFF.
- Do not disconnect multi-plug.
- Access engine control module (ECM) multi-plug terminals.
- Connect LED test lamp between ECM harness multi-plug terminal 8 and battery Fig. 1.
NOTE: The test lamp bulb must NOT exceed 1,2 watts.
- Switch ignition ON.
- Within 5 seconds of switching ignition ON: Depress accelerator pedal 5 times.
- Check that LED flashes. Note trouble codes.
- Compare with trouble code table.
Erasing trouble codes
- Ensure ignition switched OFF.
- Disconnect battery earth lead.
- Wait 10 seconds.
- Reconnect battery earth lead.
WARNING: Disconnecting the battery may erase memory from electronic units (e.g. radio, clock).
Trouble code identification
Trouble code Fault location
- 1211 Battery voltage – high or low
- 1214 Engine coolant temperature (ECT) sensor
- 1216 Throttle position (TP) sensor
- 1221 Volume air flow (VAF) sensor
- 1222 Idle air control (IAC) valve – open circuit
- 1223 Heated oxygen sensor (HO2S) – regulation
- 1224 Heated oxygen sensor (HO2S)
- 1225 Intake air temperature (IAT) sensor
- 1226 Engine control module (ECM)
- 1231 Injectors – cylinders 1 and 3
- 1232 Injectors – cylinders 2 and 4
- 1233 Idle air control (IAC) valve – short circuit
- 1235 AC/heater control
- 1236 AC compressor control
- 1243 Fuel pump relay
- 1244 Evaporative emission (EVAP) canister purge valve
- 1245 Camshaft position (CMP) actuator/engine control relay 2
- 1251 Engine control module (ECM)
- 1252 Vehicle speed sensor (VSS)
- 1254 Throttle position (TP) sensor
- 2116 Crankshaft position (CKP) sensor/ignition circuit
- 4444 No fault found