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Diagnostic System

The ECU of the TCCS is equipped with a self-diagnostic system which detects system failures or abnormalities. When a malfunction occurs, the ECU lights the "CHECK ENGINE" lamp located on instrument panel. At the same time, a corresponding trouble code is stored in ECU memory. Interpretation of the trouble codes can be performed by using an analog voltmeter.

All codes, except code "51", are stored in memory from the time of detection until the codes are cleared from the memory. The "CHECK ENGINE" lamp will go out as soon as the malfunction is cleared; but the code will remain in memory (except code "51"). Code "11" will NOT have any other code stored in memory with it.

Some trouble codes are recorded in ECU memory without causing the "CHECK ENGINE" lamp to glow. These codes are minor malfunctions which do not have a detrimental effect upon the system.

As a bulb and system check, the "CHECK ENGINE" lamp will glow when ignition switch is turned on and engine is not running. When engine is started, the lamp should go out after a short period of time. If not, a malfunction has been detected in the TCCS.