OzXFR
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Symptom Driven Diagnostics.Originally Posted by Jeff Murray
What does "SDD" stand for?
Some say it also stands for System Driven Diagnostics.
Quote:
I used SDD to put the caliper in service mode, and I have the proper windback tool- and yet all rear calipers required this extra step to retract enough to fit new pads in.
Strange. I've done this several times on an XF 5.0 SC and never had to open any bleed nozzle. Just wound in the caliper and made the swap of pads.Originally Posted by silvertonesx24
Just to help out anyone who is having trouble with it, I have a XJ 5.0 SC and XKR 4.2 SC and the process is pretty much the same on all of these (XKR has torx instead of hex socket). But on all 4 rear calipers, retracting that piston required cracking the bleed nozzle (10mm) to relieve pressure enough to be able to retract the piston.I used SDD to put the caliper in service mode, and I have the proper windback tool- and yet all rear calipers required this extra step to retract enough to fit new pads in.
OzXFR
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Much the same here, I have changed the rear pads a few times across XFS, XFR and F-Type and all I have ever done is draw a bit of fluid out of the brake fluid reservoir to ensure it didn't overflow when I wound or pushed the pistons in. Each time I need not have bothered as the level in the reservoir hardly budged anyway which I put down as due to the "old" pads being not all that worn (maybe 1/2 worn max) so the pistons didn't need to go very far back in.Originally Posted by BritCars
Strange. I've done this several times on an XF 5.0 SC and never had to open any bleed nozzle. Just wound in the caliper and made the swap of pads.
DGL
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Originally Posted by BritCars
Strange. I've done this several times on an XF 5.0 SC and never had to open any bleed nozzle. Just wound in the caliper and made the swap of pads.
Did my rear pads on a 2014 XKR over the winter. Hardest part was ordering the correct pads. Even the dealer sold me the wrong pads. My XKR uses the same pads as the XKR-S. I used an Autel AP200 dongle to retract the pistons and put the calipers in service mode, and a manual adapter kit to completely scew in the pistons. There was no need to relief pressure through the bleed screw. However, one must unscrew the reservoir cap. I also was mindful of any overflow from the reservoir and never had to remove any fluid. Although, my pads were not severely worn. I reused the original sensor.
edobernig
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Oct 8, 2025
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I used SDD to put the caliper in service mode, and I have the proper windback tool- and yet all rear calipers required this extra step to retract enough to fit new pads in.
Not to state the obvious, but did you remove the cap on the master cylinder before winding calipers back? I usually suction out remaining fluid from the master cylinder as part of brake service and install new fluid on completion. Never had this issue.Originally Posted by silvertonesx24
Just to help out anyone who is having trouble with it, I have a XJ 5.0 SC and XKR 4.2 SC and the process is pretty much the same on all of these (XKR has torx instead of hex socket). But on all 4 rear calipers, retracting that piston required cracking the bleed nozzle (10mm) to relieve pressure enough to be able to retract the piston.I used SDD to put the caliper in service mode, and I have the proper windback tool- and yet all rear calipers required this extra step to retract enough to fit new pads in.
Quote:
Yes, I always do this. Master Cylinder Cap off and shop towel to collect any possible overflow. No removal of fluid though (until bleed)Originally Posted by edobernig
Not to state the obvious, but did you remove the cap on the master cylinder before winding calipers back? I usually suction out remaining fluid from the master cylinder as part of brake service and install new fluid on completion. Never had this issue.
On both the XKR and XJ, rear caliper wouldn't retract until the bleed screw is released.
Quote:
The XFR workshop manual does not mention this as a part of the Brake Bleeding process. So I am assuming that it would not be needed.Originally Posted by Jeff Murray
How do you bleed the anti-lock braking system valve body? Because this is a separate system from the regular bleeding of the Master cylinder and associated tubing to the wheels.
