Quote:
Originally Posted by Steve G
Changed rear brake pads on my 2010 F10 520d yesterday. You don't need a computer to do it. See metod below, hope it helps.
F10 BMW 520d 2010 Onwards Rear Brake Pads Replacement Procedure
No computer system is required.
Make sure front wheels are blocked front and rear. With car jacked up and rear wheel removed, start the engine and release the handbrake button which will release the handbrake at the rear callipers. Turn off the engine. The handbrake will remain off.
Off Side Rear Brake Pads Replacement
Remove EMF brake actuator electrical cable by unplugging, release cable from bracket and unclip further back to move cable away from the work area.
Detached EMF hand brake actuator by unscrewing 2 small torx bolts (star key bolts, not Allen key bolts); one of these bolts will hold the cable bracket, remove actuator from calliper. Rest actuator on suspension wishbone as it still has cables attached.
Remove floating central section of calliper that contains the piston, by removing 2 x 13mm bolts that are bolted through to the 2 small rubber gators. Take care not to damage the pad wear sensor on the off side rear wheel. Rest this section on a tall item (wooden block or something similar) to avoid putting undue pressure on the brake hose.
Remove brake pads sideways. On off side inner pad carefully release pad wear sensor with screwdriver (it just pops out). Remove metal shims and replace with new or if no new ones available clean up existing shims with wire brush and replace. Attach pad wear sensor to new inside pad and install into place, install outer pad.
On central calliper at the rear of the piston where the actuator spline fits, turn spline clockwise with small tool until it comes to a stop (tried turning anticlockwise as advised by someone but ended up pushing piston out even further). Then use a pressure clamp and gently squeeze piston back into calliper body. Slide central calliper into position back over pads. Replace 2 x 13mm bolts and tighten.
Offer up EMF hand brake actuator and align spline, when located correctly, actuator will be flush to rear of calliper. Replace cable bracket, replace and tighten 2 x torx bolts (star key bolts). Re-plug actuator cable to actuator. Replace actuator cable and pad wear cables into bracket. Re-clip cable further back. Replace wheel and lower to ground.
Near Side Rear Brake Pads Replacement
Repeat procedure for near side brake pads replacement. Note that there is no pad wear sensor on this side, therefore when the EMF handbrake actuator is unbolted it can be removed and laid on the ground. Continue to follow the above procedure.
Handbrake and footbrake operation
When pad replacement is complete and car is on ground, press footbrake pedal a few times. With foot on footbrake, start car and activate handbrake button a few times which will set EMF brake into working order. With handbrake released you will find the brake auto hold also works correctly.
Job is complete. Now for a test drive.
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Many thanks for this Steve. Saved my bacon - I'd never have worked out how to back off the park brake (EMF) without this.
I'd add a couple of refinements to your operation:-
- You need a 15mm spanner to hold the back nut on the calliper as you undo the 13mm nuts.
- I found it easier to unbolt the calliper bolts and remove the assembly before removing the EMF as the EMF bolts are easier to access that way.
- It is possible to bolt the EMF actuator on 180 degrees out if you do it before refitting the assembly - be aware!
- The EMF piston is easily wound out (clockwise!) using a 7mm allen key.
- You need to have the handbrake OFF in order to reset the pad wear indicator.
- The handbrake and auto-hold all just reset automatically.
The offside (1st one and with sensor) took around 1h15 from jacking up to finish, but I was being cautious - as you should first time! The nearside around 30 minutes all in (easier as no sensor + knowing what I was doing)
The wear on all 4 pads was wildly different - Offside outer - 4mm and a visual inspection made me swear at the pessimistic warning. The offside inner (with the wear sensor) was about 3.5mm, so I was equally annoyed. However, the nearside outer was 3mm and inner 0.5mm - all but gone and only 170 miles past the "service now" warning.
I can only assume that this is due to TC operation on the nearside pulling from left hand junctions perhaps? Whatever, I assume that in Germany the right side wears first, hence I assume why they place the only sensor there. So it kind of works for the UK, but do NOT rely on a visual indication from the outer pads as the inner pads wear first, the nearside especially in my case (others have indicated the same). So if you drive on the right, perhaps it comes up too early - if the sensor side had been the lowest wear, it was only 80% worn. (11.5mm starting)
I assume that in the (BMW) workshop they have a command to wind back the EMF electrically and don't need to remove the EMF actuator. Unless someone knows of a canny way to wind it off electronically - that would make the job even easier as this is the most fiddly bit.
Mine lasted 39,150 miles to the "service now" indication, having started life with 30,000 miles default life expectation, which counts down 1:1 mile by mile until 4000 (I think) and then waits for the wear sensor to be contacted and then goes down according to actual wear. Oddly, on reset it's starting point is 43,000 miles - but either way the sensor will come into play when it needs to.
The reset menu is found by (I think) pressing the BC button on the indicator stalk, holding in the trip reset button in the instrument pod until you see a service picture, scrolling through by tapping the reset button until you reach "brake pads" and then hold for seconds until it asks if you want to reset, tap reset for yes and then hold for seconds until "resetting" shows. And it's done.