Shimano Power Meter Troubleshooting
Troubleshooting firmware, connection, and cadence magnet problems with the FC-R9100-P power meter crankset.
Troubleshooting firmware, connection, and cadence magnet problems with the FC-R9100-P power meter crankset.
The DURA-ACE FC-R9100-P Power Meter Crankset is exceptionally accurate and reliable, but like all bicycle components, some
riders will occasionally experience difficulties with the part. The vast majority of these issues will fall into one of three categories:
a firmware problem, a connection problem, or a problem with the magnet. This guide will provide a troubleshooting procedure that
quickly and efficiently addresses all three of these possibilities.
Firmware Problems
Firmware problems most often manifest in difficulty in pairing the crankset to a cycling computer, difficulty completing zero offset
calibration, or strange power readings.
1. Perform a hardware reset by plugging the crankset in to charge it, then holding the button for three seconds until the solid lights
blink to confirm the reset – this will also reset the passcode
2. Connect the FC-R9100-P to the E-TUBE PROJECT Mobile App as detailed in the standalone “Connecting to the
E-TUBE PROJECT App via Bluetooth® LE”
a. If an error message stating “The left crank connector may be detached” appears, proceed to the section below regarding
Connection Problems
b. If the crankset’s firmware has been corrupted, an option to rewrite it will be offered on connection –see screenshot 1
3. Confirm that the firmware is up to date – if necessary, refer to the “Updating Firmware Via the E-TUBE PROJECT Mobile App”
guide and update the firmware to the latest version
4. Perform a zero offset calibration by placing the crankarms perpendicular to the ground, removing all external loads, and tapping
the “zero offset calibration” button
5. When finished, exit by tapping the menu icon in the upper right corner and then selecting “Disconnect Bluetooth® LE” – see
screenshot 2
6. Confirm that the cycling computer supports pairing with the FC-R9100-P by consulting the manufacturer’s instructions
7. Confirm that the cycling computer is using the most current version of firmware available – update the firmware if necessary
8. Reconnect and test – if the problem persists, continue to the next section
Connection Problems
In this instance, the problematic connection in question is that between the electronics housed in the non-drive-side crank arm and
those housed in the drive-side. This is often, but not always, evidenced by an error message displayed when attempting to connect
the crankset to the E-TUBE PROJECT Mobile App – see screenshot 3.
1. Remove the plastic outer cap from the non-drive-side crank arm
2. Unsnap and remove the connector very gently and without pulling on the wire
3. Carefully inspect the wire for any kinks, crimps, breaks, or discoloration – a damaged wire will require replacement of the non-
drive-side crank arm
4. Using a flashlight, carefully inspect the connector on the wire as well as the connection port on the spindle for the presence of
any grease or signs of any kind of corrosion or other contamination – contaminated connections generally require replacement
of the entire crank
5. Use the TL-FC40 to make sure that one of the “gaps” around the top of the crank arm fixing ring lines up directly with the small
relief on the spindle and the wire
6. Reconnect the wire, making certain that the connector “snaps” into place and that the wire lays flat in the gap of the crank arm
fixing ring and relief on the spindle and is not being crushed by the plastic outer cap.
7. Reinstall, reconnect, and test – if the problem persists, continue to the next section
Magnet Problems
The FC-R9100-P utilizes sensors built into the crank itself to measure both power and cadence, but the cadence sensor requires
an external magnet to use as a reference point. If the cadence sensor is getting unexpected readings, the information transmitted
by the crank will be unreliable.
1. Remove the crankset from the bike, using the TL-FC40 to remove the fixing ring
2. Use the Magnet Setting Tool included with the FC-R9100-P to verify proper placement of the magnet
“button” housing on the drive-side chainstay, seat tube, or down tube.
3. Use a small hex wrench or other magnetic material to verify that there is a magnet underneath the black or white “button”
housing
a. If it “sticks”, the magnet is present
b. If it does not, then there is no magnet
4. Being careful not to scratch or damage the frame, use the same method to check and make sure there are no additional magnets
inside the frame – this is particularly common on the Trek Emonda and Domane SLR, which often have magnets preinstalled
inside the seat tube
a. If there is a magnet pre-installed in the frame, remove the SHIMANO magnet and rely on the existing magnet
b. If there is no magnet in the frame and also no SHIMANO magnet on the chainstay, install a magnet as per the instructions
riders will occasionally experience difficulties with the part. The vast majority of these issues will fall into one of three categories:
a firmware problem, a connection problem, or a problem with the magnet. This guide will provide a troubleshooting procedure that
quickly and efficiently addresses all three of these possibilities.
Firmware Problems
Firmware problems most often manifest in difficulty in pairing the crankset to a cycling computer, difficulty completing zero offset
calibration, or strange power readings.
1. Perform a hardware reset by plugging the crankset in to charge it, then holding the button for three seconds until the solid lights
blink to confirm the reset – this will also reset the passcode
2. Connect the FC-R9100-P to the E-TUBE PROJECT Mobile App as detailed in the standalone “Connecting to the
E-TUBE PROJECT App via Bluetooth® LE”
a. If an error message stating “The left crank connector may be detached” appears, proceed to the section below regarding
Connection Problems
b. If the crankset’s firmware has been corrupted, an option to rewrite it will be offered on connection –see screenshot 1
3. Confirm that the firmware is up to date – if necessary, refer to the “Updating Firmware Via the E-TUBE PROJECT Mobile App”
guide and update the firmware to the latest version
4. Perform a zero offset calibration by placing the crankarms perpendicular to the ground, removing all external loads, and tapping
the “zero offset calibration” button
5. When finished, exit by tapping the menu icon in the upper right corner and then selecting “Disconnect Bluetooth® LE” – see
screenshot 2
6. Confirm that the cycling computer supports pairing with the FC-R9100-P by consulting the manufacturer’s instructions
7. Confirm that the cycling computer is using the most current version of firmware available – update the firmware if necessary
8. Reconnect and test – if the problem persists, continue to the next section
Connection Problems
In this instance, the problematic connection in question is that between the electronics housed in the non-drive-side crank arm and
those housed in the drive-side. This is often, but not always, evidenced by an error message displayed when attempting to connect
the crankset to the E-TUBE PROJECT Mobile App – see screenshot 3.
1. Remove the plastic outer cap from the non-drive-side crank arm
2. Unsnap and remove the connector very gently and without pulling on the wire
3. Carefully inspect the wire for any kinks, crimps, breaks, or discoloration – a damaged wire will require replacement of the non-
drive-side crank arm
4. Using a flashlight, carefully inspect the connector on the wire as well as the connection port on the spindle for the presence of
any grease or signs of any kind of corrosion or other contamination – contaminated connections generally require replacement
of the entire crank
5. Use the TL-FC40 to make sure that one of the “gaps” around the top of the crank arm fixing ring lines up directly with the small
relief on the spindle and the wire
6. Reconnect the wire, making certain that the connector “snaps” into place and that the wire lays flat in the gap of the crank arm
fixing ring and relief on the spindle and is not being crushed by the plastic outer cap.
7. Reinstall, reconnect, and test – if the problem persists, continue to the next section
Magnet Problems
The FC-R9100-P utilizes sensors built into the crank itself to measure both power and cadence, but the cadence sensor requires
an external magnet to use as a reference point. If the cadence sensor is getting unexpected readings, the information transmitted
by the crank will be unreliable.
1. Remove the crankset from the bike, using the TL-FC40 to remove the fixing ring
2. Use the Magnet Setting Tool included with the FC-R9100-P to verify proper placement of the magnet
“button” housing on the drive-side chainstay, seat tube, or down tube.
3. Use a small hex wrench or other magnetic material to verify that there is a magnet underneath the black or white “button”
housing
a. If it “sticks”, the magnet is present
b. If it does not, then there is no magnet
4. Being careful not to scratch or damage the frame, use the same method to check and make sure there are no additional magnets
inside the frame – this is particularly common on the Trek Emonda and Domane SLR, which often have magnets preinstalled
inside the seat tube
a. If there is a magnet pre-installed in the frame, remove the SHIMANO magnet and rely on the existing magnet
b. If there is no magnet in the frame and also no SHIMANO magnet on the chainstay, install a magnet as per the instructions
