Your car may have a "Shift Indicator" light system. I don't know how the system is supposed to work, but my Volvo Wiring Diagram for 1987 240 shows the component parts.

You might look for a switch on the clutch pedal similar in location and action to the brake light switch. There is also a control unit that looks like a small box similar in appearance to the headlight stepping relay. It looks to be located up above the driver's left toe. There is a BN-W wire from Fuse #9, and what looks like a harness with six other wires in it. Two wires "peel off" to the clutch switch, SB (Swedish for black) and BN.

The control unit relates engine speed (signal from tach) and vehicle speed (signal from speedometer) to tell you - via the arrow - that you're in the wrong gear.

Look at www.volvocars.com/lit to see if an owner's manual is available.

Good Luck,

Bob

:>)