There is the possiblility of excessive chafing of the insulation of the positive and negative battery cables.
Electrical system
Volvo 744 Electrical problems by year
2 complaints filed with NHTSA about the Volvo 744's electrical system. Dead batteries, warning lights, wiring, alternators, infotainment and electronic module failures.
Electrical complaints by model year
Electrical recalls
Latest 744 electrical complaints
While parked waiting for a friend the dashboard started smoking and then bursted in to flames,no one was injured. The inside of the car was a total loss. Consumer has yet to contact the dealer. Please provide any further details. *Ak
BATTERY CABLES FAILED PRIOR TO RECALL NOTICE.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) complaints and recalls, checked daily. Complaints are owners' own reports and are not verified. How we use the data