1. Check the Child Lock: Ensure that the child lock is not engaged. The child lock switch is usually located on the side of the rear door. If it's engaged, disengage it.
2. Reset the Electrical System: Sometimes, a glitch in the electrical system can prevent the door from unlocking. Try resetting the electrical system by disconnecting the car battery for a few minutes and then reconnecting it.
3. Access through Another Door: If possible, try to access the vehicle through another door and engage the interior release mechanism directly. Locate the interior door handle release lever or cable and attempt to manually unlock the door.
4. Use the Key: If all else fails, you may need to use the metal key to unlock the door. Insert the key into the door lock cylinder and turn it to unlock the door.
If none of these methods work, you may need to take your vehicle to a professional mechanic or auto locksmith who can further diagnose the issue and access the passenger door. They have specialized tools and expertise to handle complex lock issues. Ensure your door is unlocked by a qualified professional to avoid causing damage to the lock mechanism.
