2001 Volvo S80 engine system service required

[Matty Moo]

I think it was TCU codes that it couldn't access.

[naperboiler]

I had the same error on a 99 S80 T6. The problem was the brake pedal position sensor. When you have the error present, your cruise control may not work. I removed mine, disassembled it and re-soldered the broken solder joints. Make sure you bring the vacuum assist to atmospheric pressure before you pull the sensor or you are likely to lose the 0-ring that seals the sensor.