One problem related to software has been reported for the 2005 Volvo XC90. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Volvo XC90 based on all problems reported for the 2005 XC90.
Brakes lights always on. Took car to dealer and they advised that water had leaked into cem module and main wireharness and required replacemnet at a cost of $7000. Known issue to Volvo with service bulletin sent to dealers. Found independent Volvo repair shop willing to replace module only (software download from dealer) and clean build-up on harness connectors. Requiring removal of part of dash, driver seat. Took 4 days at repair shop. Repair completed for under $2000.