Re: 1987 Teka
If your starter is locked, indicator lights will dim noticeably when you try to start feeding battery current into a dead short.
Check starter brushes.
Also, look for loose or corroded connections. A corroded connection might pass enough current to illuminate an indicator lamp, but not enough to spin the starter. <--The same holds true for frayed wires. Say you have a wire with 20 strands and 15 of 'em are broken due to flexing or somesuch. Those 5 remaining strands are gonna get hotter'n a pistol and resist current flow when a high demand - like a starter, is placed on it.