If your senior lender forecloses on you property in California.
The junior lender no long has security to foreclose upon.
Junior lenders with no security are called sold out Juniors.
Sold out juniors may be able to proceed against you to collect the balanced owned plus costs and fees.
If you have two loans talk to an attorney.
You may wish to keep the senior loan active while negotiation and short payoff or loan mod with the second.