I've had this car for 3 years. It had the break system failure and anti skid warning on the car when I first bought it. If I pull in turn the car off it can take anywhere from the first turn of the key up to half an hour for the car to start again I'll drive for 5 min and it will happen again with the break system failure. Sometimes the car will lose all power and I'll be forced to pull in other time the car will keep driving but all my dials will drop so I wont know what speed I am doing or how much fuel I have left. I brought it to a reputable mechanic who said it was an ecu issue ( I am completely clueless when it comes to electronics on cars) that resolved the problem for 2 weeks then back to the break system failure again. This time he said it was the CEM unit, again it worked fine for a few weeks only this time I could not get the car to start at all. So it went back to the mechanic. After a long argument with him and treating to take him to small claims for not fixing the issue I paid him to fix he gave me back the car. I changed the wish bones and breaks myself on the car as I noticed they were worse for ware. For 2 years I drove the car with no issues what so ever.
Now tho about 2 weeks ago the break system failure warning came back. I done the usual pulled in turned the car off and after a few attempts it would start again and the warning would disappear till the next day. This week though its becoming more problematic as the warning will come on multiple times while I am driving, sometimes I am forced to stop and turn the car off other times it will allow me to continue driving and the warning will disappear but the anti skid warning will appear and put the car in limp mode. Today tho I had the same break system failure happen a few times while travelling to work but now it is also accompanied with the engine system service required warning. I am wondering if anyone else has experienced this issue and how to resolve it keeping in mind I am not great with electronics in cars

 

have the car scanned for diagnostic codes - common causes for brake fault messages include wheel speed sensors, the ABS controller board, ABS pump, wire harness/connectors, steering angle sensors, low brake fluid level and a few other things. When you say "lose all power" do you mean the car stalls or just that it can't go anything faster than a crawl - suggesting the car is in limp mode.

 

Apologise for the confusion as this is my first volvo. When the car loses power it wont go any faster than a crawl less than 5mph. While the anti skid warning is on there is a delay between changing gears and power to the accelerator I assumed this was the limp mode

 

No one will be able to diagnose the likely problem based on just the above - you need to have the OBD trouble codes read, and let us know what they are. That (hopefully) will provide a lot more info about which system(s) is having problems.

 

Yep, sounds like the car is in limp mode to protect the car (and you), which will likely have diagnotic trouble codes that need to be scanned. You may need to have a better OBD2 reader (say something a shop would use) to read the transmission and ABS codes. They will tell you things like whether a wheel sensor is acting up (and which one), whether the ABS controller is properly communications with the transmission computer and onwards to the main ECU.