|| Procedures || Data ll
Testing for ECU Fault Codes.

Any engine management fault is logged by the ECU and stored as a “fault code”. This gives the technician the ability to repair a fault by being able to identify the source of the problem quickly and easily.

Many overseas models had a Check Engine Light (CEL) to simplify the observation of stored faults. The Eunos range did not incorporate a CEL, so fault codes need to be read through the temporary installation of test equipment connected to the Diagnostics Box within the engine bay. The lack of a CEL also means the driver may be unaware of a fault that may be inadvertently affecting their fuel consumption, available power, etc. It is recommended to “pull” fault codes on a regular basis to ensure your car is running to its designed optimum efficiency.

A common query among Eunos owners is how to pull the codes and what equipment to use. There seems to be a misunderstanding that the solution will run into significant money but the truth is that the equipment can be made cheaply and still be just as effective. All that is needed is an LED (with resistor to operate for 12 volts DC) with approximately 300mm of light cable soldered to the legs and a small jumper wire (or paper clip). It is suggested an alligator clip be fitted to the positive leg for ease of fitting to the vehicle.
** Note - these are available from teamEunos for a nominal fee and comes comple with instructions.

Once you have purchased (or made) the above LED tester, download and print the following instructions to retreive any fault codes:

Testing for ECU Fault Codes.pdf