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CHECK GEARBOX warning lamp

CHECK GEARBOX warning lamp


When a fault occurs in the automatic transmission or TCM control module, the CHECK GEARBOX warning lamp in the main instrument unit will go on. If only a minor fault occurs, the CHECK GEARBOX lamp will go on during the second driving cycle, although the diagnostic trouble code will be generated during the first driving cycle.

The lamp is supplied with current in the main instrument unit and grounded by the MIU's control module.

If a fault occurs in the transmission, TCM will send bus information “CHECK GEARBOX ON”.

The main instrument unit's control module grounds the output for the CHECK GEARBOX warning lamp, which then lights up.

The lamp goes out when the TCM sends the message “CHECK GEARBOX OFF”.

When the ignition is switched on, the TCM will keep the lamp on for about 3 seconds and if no fault is detected the lamp will go out.