Swapping rear rotors to RB setup, ran into issue, question inside.,

[Sam1]

Picked up a set of the RB rotors and pads. Got the fronts on with no issue, minus what I think is the dust shield scraping on one side.. will address that tomorrow.

Rears: put vehicle in tow mode, unhooked power to e brake at the rotor, removed ebreak motor from rotor. Everything disassembled fine. Put new rotor on, compressed piston and put new pads in. Caliper won't fit over the rotor, even with some light tapping with a dead blow hammer. Put OEM rotor on there, caliper with rb pads won't fit. Put OEM pads in, they slide right over the OEM rotor easily.

Took apart, tried to compress the piston again, it wouldn't move anymore. And the RB stuff would not fit after the second try.

Does anyone know if there's a trick to compressing the piston even more? It looked like it may have 1/8" sticking out, but it's not compressing anymore. I've done tons of brake jobs, but never one with an electric e brake system.

Went back to OEM with zero issues, so the e brake was definitely not engaged.

 

[MP3Mike]

I thought the pistons have to be screwed in, not compressed.

 

[destructure00]

The parking brake screw needs to be retracted before you can compress the piston.

Easiest way I've found...get a normal 9v battery and two wire leads. Connect the negative terminal on the 9v to the pin in the parking brake motor on the flat side of the connector housing, and connect the positive terminal to the pin on the rounded side. Let it run for a couple seconds, then you should be able to compress the piston further.

 

[Sam1]

The parking brake screw needs to be retracted before you can compress the piston.

Easiest way I've found...get a normal 9v battery and two wire leads. Connect the negative terminal on the 9v to the pin in the parking brake motor on the flat side of the connector housing, and connect the positive terminal to the pin on the rounded side. Let it run for a couple seconds, then you should be able to compress the piston further.

Thank you, will give that a shot this weekend.