Check the cable terminal locking tabs
WARNING: This page is about a different car, the 2002 Volvo C70, 2001 Volvo C70, 2000 Volvo C70, 1999 Volvo C70, and 1998 Volvo C70. However, it is still accessible from the selected car via links, so may be relevant.
If the cable terminal has locking tab/locking tabs, check that they are not damaged or pressed inward so they will not engage when the terminal is inserted in a housing.