Erasing HomeLink buttons

To erase the three programmed buttons (individual buttons cannot be erased):
• Press and hold the two outer HomeLink buttons until the indicator light begins to flash-after 20 seconds. Release both buttons. Do not hold for longer that 30 seconds.

HomeLink is now in the train (or learning) mode and can be programmed at any time beginning with Step 1 in the Programming section.
See also:
Car finder
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When the engine starts, the idle RPM runs faster to warm the engine. If
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