Ecu "A"
- Different vehicle applications require different ECUs. Checking ECU identification code ensures vehicle is equipped with correct ECU. At the factory, ECUs are coded to identify them for their correct vehicle application. ECU identification code represents vehicle application.
- Factory performs coding at ECU connectors "B" and "C". First 3 digits of code apply to terminals No. 14, 16 and 19 of connector "B", and fourth digit of code applies to terminal No. 9 of connector "C". If ECU grounds one of these circuits, "0" will be displayed. If ECU does not ground the circuit (leaves the circuit open), "1" will be displayed.
- To determine if ECU identification code is correct, check displayed ECU identification code to see if it matches vehicle application. See ECU IDENTIFICATION CODES (ECU "A") table. If displayed code does not match application, check routing of wires at ECU connector. Relocate wires in correct terminals if necessary. If wires are correctly routed, replace ECU.
ECU IDENTIFICATION CODES (ECU "A")
| Code | Application |
|---|---|
| 1010 | With M/T; Without EGR |
| 1111 | With M/T & EGR; Without EGR Temp. Sensor |
| 1011 | With Calif. Emissions, M/T, EGR & EGR Temp. Sensor |
| 1110 | ECE Version W/ M/T; W/O Heated O2 Sensors, EVAP & EGR |
| 0010 | W/FWD & A/T; Without EGR |
| 0111 | W/ FWD, A/T & EGR; Without EGR Temp. Sensor |
| 0011 | W/ Calif. Emissions, FWD, A/T, EGR & EGR Temp. Sensor |
| 0110 | ECE Version W/ FWD & A/T; W/O Heated O2 Sensors, EVAP & EGR |
| 1000 | Quattro With A/T; Without EGR |
| 1101 | Quattro With A/T & EGR; Without EGR Temp. Sensor |
| 1001 | Quattro W/ Calif. Emissions, A/T, EGR & EGR Temp. Sensor |
| 1100 | W/ ECE Version & A/T; W/O Heated O2 Sensors, EVAP & EGR |
| 0000 | Diagnostic Trouble Code (DTC) |
| 0001 | Diagnostic Trouble Code (DTC) |
| 0100 | Diagnostic Trouble Code (DTC) |
| 0101 | Diagnostic Trouble Code (DTC) |