CFDI40116
El campo TipoCambio no se debe registrar cuando el campo Moneda tiene el valor XXX.
In English TipoCambio must be left out when Moneda is XXX (no currency).
error: the document is invalid
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.