The electronic portion of the ignition switch may malfunction, causing some dash lights to stay on. When this happens, a wiggle of the ignition key should temporarily return everything to normal.
Car Problem Reports
Volvo 850 Dash Lights May Stay on Due to Malfunction in Ignition Switch
Volvo 850 Problem
Average Mileage: 183,500 mi (180,000 mi - 187,000 mi)
Dash lights come on during the initial startup but goes out and stays out.
Contacts to ignition key switch erratic; if push up on key usually restores. Symptom obvious when shift lock fails to release from Park. Not repaired, just wiggling as needed.
Visitor, 1996 Volvo 850
Intrument cluster light intermittently come on when starting the car with the headlight switch off. Self correcting after a short time.