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The ABS doesn't need to be "de-pressurized" on a Volvo. There are a few cars out there that have the master cylinder/hydro-boost/ABS pump as a unit. These are the ones for that precaution.
All you need do is obtain a piece of 1/4" I. D. clear vinyl tubing and a coke bottle. Have 2-3 pints of the proper brake fluid on hand.
IF you are changing a part and air is already in system, then the order is important. IF you are doing a flush/bleed then the order is not important.
Remove the master cylinder reservoir and dump it out and add a bit of fluid and agitiate it and dump it out to get all the old fluid out. Install resevoir and then fill with fluid.
Go to whichever caliper you care to do first and loosen the bleeder 1/8 turn. Attach the clear tubing and place end in coke bottle. Add just enouigh clean brake fluid to coke bottle so that tube is below the fluid level. Get in car and pump pedal slowly to its stop point 10 times. Get out and check/top up fluid. See if the fluid in tube is clear, if so close bleeder and remove tube. If not, pump five more times. Go to next caliper and repeat until all have been done.
The bleeder screw opening should be just enough to allow fluid to pass out. This can be determined by feeling resistance as you push pedal. If the pedal goes to floor w/o resistance then you should turn in bleeder screw 1/16 turn. The idea is to do have resistance to the master cylinder suction pulling fluid back in through tube. This way the fluid will be pulled from reservoir on upstroke of pedal and you will not need to do the pump x times, hold, open screw, close screw, pump x times thing.
I have done this for 25 years and never had a problem and never had arguments with girlfriends, co-workers, family members as I didn't need their assistance. IF you have a buch of air in system then you will have to do the pump-open-close pump routine. You never get the fluid completely changed on ABS cars as some fluid is in a storage accumulator that is not accessible. If you periodically change fluid this is never an issue as the fluid left in these areas will be circulated eventually through much of the system and it will be diluted by the clean fluid and will pose no problem.
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