Not sure what those codes are for, but wonder if your PNP switch still needs to be adjusted. Volvo dealerships usually have a special tool to get the switch postioned correctly. It most certainly can be done without the tool, but it requires a little trial and error.

I use the reverse lights as a guide, with car blocked safely so it cannot roll away. This is important because someone will be under the car. Place gear selector into reverse, ignition on, have a helper look for the reverse lights, you want to loosen the pnp switch's bolt on the slotted hole of the switch, by pivoting the switch, find the two farthest points on the switch that light up the reverse lights, then place switch in the middle of those two spots and tighten.

First test is to position gear selector in park, firmly place foot on brake pedal and try starting engine. Next test place car in reverse and try starting engine. You want it to start in park but not in reverse. If any of those fail, then move the switch a touch one way, then repeat tests. If it still fails, then move the other way (2X the first movement) and repeat tests. But the middle of the reverse light sweet spot, usually gets it really, really close to functional.

DanR '94 964 387,000 miles (153,000 on the new engine)
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DanR