A couple of days ago, the message "ENGINE SYSTEM SERVICE NEEDED" appeared in the dashboard display of my 2007 (not latest shape) V70 D5 - accompanied by a yellow warning triangle.
When the message was displayed, the car seemed to be in "limp home mode", and wouldn't go any faster than about 40mph.
I discovered that pressing the READ button suppressed the message, and that the car would then perform normally. However, the message would re-appear every time the ignition was turned on after a stop.
However, today, I did a longer journey, not stopping the engine for 50 or 60 miles. Upon restart, the message did not appear - and has not appeared after subsequent re-starts. According to the handbook, pressing the READ button stores any messages in the memory - and they can be re-read later by pressing it again. However, when I now press READ, it says NO MESSAGES!
Can anyone throw any light on the possible cause of all this? Was this a real fault, or just a spurious reading from a sensor - which initially latched in the system but re-set when it didn't re-appear after X miles? If I take it to a dealer and have the system memory analysed, are they likely to discover anything, or am wasting my money?