You can reset the code (assuming US car) by the following:

1) turn the ignition on so all instrument cluster lamps are illuminated,
2) at the right side of the engine compartment near the battery, press the button on the diag panel for about 4 sec,
3) read the number of flashes; sb '9' for "INTAKE AIR TEMPERATURE SENSOR, OPEN/SHORT CIRCUIT".
3) Within 20 sec, press and hold the button for 8-9 sec.
4) Shut the ignition off for 10 sec.

This method eliminates the car radio code reset and it's quicker. In fact any code from the DIAG module can be reset by this method.

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Regards . . . . JimF
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'94 S500 Cpe

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