On my BMW 528i while driving radio stops working,

bad english accepted i come from the east end of london originally where english is the third language ,so what iam reading here is you have a problem with horn and the lights ,Now on this model if my memory serves me correct the brake lights will come on with the handbrake on ,but if its a auto version then the brake lights could be affected cruise control and what i think without a look myself is that the wires on the bottom of the steering wheel for the cruise and the radio horn ect run through the steering column and somehow they are damaged or twisted up and the only way is to remove the steering wheel to have a look ,to do this you must disconnect the battery first because if the airbag goes off accidently and your head is in the way then your dead .To get the stering wheel off you will have to remove the airbag unit first ,think its two torq 20 screws but it could be a 7mm headed nut ,remove the airbag then unplug it and then you can undo the big nut in the middle ,cannot remember the size of the nut though but once its off then the steering wheel comes off but its on a splined shaft so it may need a puller to get it off but i often use a piece of wood under a spoke and hit it with a 2kg hammer ,doesnt always work first time but normaly it does then you will tracks for the different controls .

• Replace rear pads and wear sensor.
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Hold milage reset til you see test then toggle through it pro forms test and resets. Check YouTube for further info

Turns out it was the ignition switch (Various lights and radio)and clock spring (air bag light). Both were simple replacements with common hand tools. Simply go to youTube and watch any of the number of videos. Clock spring took me 20 minutes to replace. The ignition switch 45 minutes. Just remember to unhook your battery before you begin.

This is due to a broken clockspring behind the steering wheel. It works as a constant contact for all acessories on the steering wheel to include the air bag system. It is a simple ribbon of wire to allow for turning of the wheel incased in a plastic housing that shouldn't be messed with. If you mess with it internally, you run the risk of the airbag deploying in your face!! It is best purchased from BMW.

You will need to get it diagnosed to see which wheel sensor is bad.

If both the abs and the brake light are on on the speedo dont work them the module is bad.

Also make sure the tire pressures are the same

Since both problems surfaced at the same time...this indicates they are on the same circuit. Since both features would not quit working at once, I'd bet the farm that neither is getting power. I'd start at the fuse box, If all good there, maybe a relay. Also check all other power functions if these solutions don't work to see if anything else is effected.

I had that problem. I have a 1997 528i, the plug on the side of the drivers seat under the plastic panel came unplugged. I had to just simply plug it back in, steering wheel adjusted and seat moved too. Maybe this is your problem too.

Read the owners manual on resetting your door control seat preference this will include steering column and pedal adjustment if installed on your 7.

sounds like brake booster not working
check vacuum hose that goes to booster is ok and not leaking
engine off
pump up brake pedal several times
hold brake pedal down
start engine
pedal should sink down approx half to 3/4 way down indicating booster is working
if pedal doesnt go down when engine is running booster has leak or no vacuum supply from engine which requires great pedal effort to try and get vehicle to stop.

i think the seat control unit controls both items. check the connections at this unit to see if they are still securely attached to the unit.

i didn't know your exact model as i could not find the 08 528i and didn't know if yours was LH or RH drive. take a look at the pic and look for box #1 under the seat.

http://www.realoem.com/bmw/showparts.do?model=PU72&mospid=50127&btnr=61_2016&hg=61&fg=25