Posted: Tue Mar 12, 2019 5:27am
Ray is correct, except that it's both articles 2 and 4.2 of the driving regulations that are applicable.
Many town halls also have their own ordinances including the topic; for example, for Orihuela it is:
http://www.orihuela.es/wp-content/uploads/2010/03/trafico.pdf
The legislation doesn't specifically refer to washing or repairing a car on the street. Instead, the scope is wider and refers to the possible deposit of contaminants or otherwise affecting the safety of the road. Even clean water on a street that has been dry for some time can make the surface extremely slippery, as any cyclist will know.
In some ways it's analogous to running out of petrol. That's not specifically mentioned in the legislation, but it's covered by the description of driving without due care and attention.