Using the Digital Dashboard to Decipher EFI Trouble Codes
In addition to the diagnostic scan tools, you can use the engine warning light of the Siemens dashboard to diagnose EFI problems. The digital dashboard receives signals from the MT05 ECU, and the engine warning light will flash a diagnostic trouble code (DTC) if the ignition key is switched on/off for three cycles.
When you turn on the ignition, the engine warning light will illuminate, which indicates the EFI system is operational. After the engine is started, the engine warning light will extinguish if the EFI system is working properly. However, if the engine warning light remains illuminated, it indicates the EFI system is
not working properly, and there is a system component failure.
Deciphering Diagnostic Trouble Codes
To read the diagnostic trouble code (DTC), open and close the ignition key three times in rapid succession, as follows: open/close—open/close—open. At this point the engine warning light will flash a DTC which indicates the fault in the EFI system. Refer to the fault code table below to identify the corresponding problem.
The engine warning light will emit a sequence of flashing lights. If the light flashes 10 times, the translated number is 0. If the light flashes one time, the translated number is 1, et cetera. For example, if the MAP/MAT sensor is disconnected, or the connector is shorted to ground, the engine warning light will flash in the following manner.
The engine warning light will flash 10 times: The first number of the DTC is 0
After an interval of 1.2 seconds, the engine warning light will flash 1 time: The second number of the DTC is 1
After an interval of 1.2 seconds, the engine warning light will flash 10 times: The third number of the DTC is 0
After an interval of 1.2 seconds, the engine warning light will flash 7 times: The fourth number of the DTC is 7
The resulting DTC is P0107. Referring to the chart below, we see this error code indicates a problem with the MAP/MAT sensor.
If there are other fault codes, the engine warning light will flash the next code in 3.2 seconds after finishing P0107. After all existing fault codes are flashed, the engine warning light will repeat the fault codes, in sequence, until the ignition key is turned off.