Tenants in California, by law, are entitled to rental property that is habitable. In other words, it must meet basic health and safety standards and is in generally good repair. Habitability is a function of the building codes combined with common sense workability. When a tenant is presented with a problem like a broken pipe, a failed water heater, or a defective electrical system they are granted certain statutory rights.
If a landlord or property management company fails to repair or adequately address the issue, once given proper notice, then the tenant has remedies. First, the tenant can pay for the repairs themselves and deduct the cost of the repairs from their rent. Second, the tenant can withhold rent. Third, the tenant can call the local code enforcement officer for an inspection which could lead to administrative problems for the landlord. Fourth, the tenant can file a lawsuit against the landlord. Finally, the tenant may move out without giving any further notice provided the breach of habitability is sufficient to warrant such action.