Cal. Civ. Code § 2808 : CALIFORNIA CIVIL CODE — OBLIGATIONS — OBLIGATIONS ARISING FROM PARTICULAR TRANSACTIONS — SURETYSHIP — LIABILITY OF SURETIES — Liability of surety assumed upon conditional obligation

Where one assumes liability as surety upon a conditional obligation, his liability is commensurate with that of the principal, and he is not entitled to notice of the default of the principal, unless he is unable, by the exercise of reasonable diligence, to acquire information of such default, and the creditor has actual notice thereof.