I drive a 2001 V70XC with about 175k miles on it. I generally do all the maintenance and repairs myself. A few days ago had the engine system service required light come on and I can't get it to go away. I have tried the odometer button reset that generally works. My closes Volvo dealer is almost 2hours away through the mountains. This weekend I plan on pulling the ETM and cleaning it, swapping out the brake position switch with a known good one and changing the fuel filter. Does anyone have any other suggestions on what I can start looking at? It seems to run well, has no DTC codes. The spark plugs are only a year old. What else would cause this light to stay on? Thanks in advance.