There will be an icon that asks for your coupon code. You only have 14 days though until it expires.
Follow the prompts on the machine. Enter the code when told to do so.
Put wash code in before selecting type of wash ,and you have to request wash code before you select type of wash
Enter the code when you select the car wash that you want instead of either money or your credit or debit card
Follow the touchscreen prompts where you pay for wash.
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