Shimano STEPS charger LED blinking or battery not charging: which part is at fault
ChargerShimano STEPS
Shimano's EC-E6000/E6002/E8004 chargers show one LED that blinks a fault code, and the battery answers with its own LEDs. Read both together and you can separate a dead charger, a locked battery and a bad on-bike charging adapter in a few minutes.
Warning: Shimano packs (BT-E6000/E6010/E8010/E8020/E8035/E8036) only charge from Shimano chargers. Do not force the plug: the small 2-pin charge connector bends easily and is not repairable by the user. Never charge a pack that is wet inside its case.
What you need
- The Shimano charger; the model is on the label (EC-E6000 with detachable cable, EC-E6002 with fixed cable, EC-E8004 with USB-C style flat plug for E8020/E8035/E8036)
- For on-bike charging of E6000-series packs: the SM-BTE60 charging adapter
- A known-good wall socket
- The battery removed from the bike if possible
LED patterns and what they mean
| Charger LED off, plugged into mains only | Normal for EC-E6000/E6002: no standby LED. EC-E8004 shows a brief flash at power-up. A totally dead EC-E8004 on a live socket has failed. |
| Charger LED steady red or orange | Charging. Battery LEDs count up as the charge progresses. |
| Charger LED steady green | Charge complete, or no battery detected. Check the battery LEDs to tell which. |
| Charger LED blinks once per second (slow) | Battery temperature outside the charging range. Charging paused, resumes automatically. |
| Charger LED blinks fast, or in groups | Charger fault or battery communication error. Unplug both ends, wait 10 seconds, reconnect. Persisting: charger or battery fault, continue the flow. |
| Battery LEDs all off while charger shows charging | Plug not fully seated or battery BMS not responding. Reseat once. |
| Battery LEDs: red blinking on the pack | Battery fault (protection triggered). Matches E010/E011/E013 style errors on the display. Dealer needed. |
Step by step
1. Confirm the socket and the mains lead
Test the socket with a lamp. On the EC-E6000 push the detachable mains lead fully home; on E6002/E8004 check the fixed lead for kinks near the charger body.
If OK: Go to step 2.
If not: Socket or lead. Replace the C7 lead on E6000 if it is damaged.
Test the socket with a lamp. On the EC-E6000 push the detachable mains lead fully home; on E6002/E8004 check the fixed lead for kinks near the charger body.
If OK: Go to step 2.
If not: Socket or lead. Replace the C7 lead on E6000 if it is damaged.
2. Charge the battery directly, off the bike
Remove the pack. Plug the charger straight into the socket on the pack (E6000/E6010 have it under a rubber cap on the end; E8010/E8020/E8035 on the side or end). Watch both LEDs.
If OK: Charges off the bike: charger and battery are fine. On-bike charging problem: go to step 6.
If not: Nothing off the bike: go to step 3.
Remove the pack. Plug the charger straight into the socket on the pack (E6000/E6010 have it under a rubber cap on the end; E8010/E8020/E8035 on the side or end). Watch both LEDs.
If OK: Charges off the bike: charger and battery are fine. On-bike charging problem: go to step 6.
If not: Nothing off the bike: go to step 3.
3. Check the charger fault blink
With battery connected, count the blinks on the charger LED. Slow single blink is temperature; fast or grouped blinks is a fault.
If OK: Steady charging LED but battery LEDs dark: plug not seated or pack not responding, go to step 4.
If not: Slow blink: bring the pack indoors for two hours and retry. Fast blink that survives a 10-second unplug and reconnect: go to step 5.
With battery connected, count the blinks on the charger LED. Slow single blink is temperature; fast or grouped blinks is a fault.
If OK: Steady charging LED but battery LEDs dark: plug not seated or pack not responding, go to step 4.
If not: Slow blink: bring the pack indoors for two hours and retry. Fast blink that survives a 10-second unplug and reconnect: go to step 5.
4. Does the battery show charge on its own button?
Off the charger, press the pack's button. Count LEDs (5 on most packs).
If OK: At least one LED: the pack is awake. A charger that then shows green with no charging is not delivering. Go to step 5.
If not: No LEDs: deep discharge or BMS latch. Leave on the charger for 30 minutes, retry. Still dark: verdict battery, dealer.
Off the charger, press the pack's button. Count LEDs (5 on most packs).
If OK: At least one LED: the pack is awake. A charger that then shows green with no charging is not delivering. Go to step 5.
If not: No LEDs: deep discharge or BMS latch. Leave on the charger for 30 minutes, retry. Still dark: verdict battery, dealer.
5. Swap the charger for a known-good Shimano charger
Same family: EC-E6000 or E6002 for the 2-pin round connector packs, EC-E8004 for the flat-plug E8020/E8035/E8036 packs. A dealer will test in a minute.
If OK: Charges on the other charger: yours has failed. Verdict: charger.
If not: Same fault on a good charger: verdict battery. Have the dealer read it with E-Tube.
Same family: EC-E6000 or E6002 for the 2-pin round connector packs, EC-E8004 for the flat-plug E8020/E8035/E8036 packs. A dealer will test in a minute.
If OK: Charges on the other charger: yours has failed. Verdict: charger.
If not: Same fault on a good charger: verdict battery. Have the dealer read it with E-Tube.
6. On-bike only: check the charging adapter and frame port
E6000-series packs charge on the bike only through the SM-BTE60 adapter clipped to the frame port; E8000 series use a frame port wired to the battery holder. Inspect the port for bent pins and the adapter for a cracked housing.
If OK: Port and adapter look clean: reseat the adapter until it clicks and try again with the bike switched off.
If not: Bent pin, corrosion, cracked adapter: replace the adapter (cheap) or have the frame port harness fixed. Verdict: bike.
E6000-series packs charge on the bike only through the SM-BTE60 adapter clipped to the frame port; E8000 series use a frame port wired to the battery holder. Inspect the port for bent pins and the adapter for a cracked housing.
If OK: Port and adapter look clean: reseat the adapter until it clicks and try again with the bike switched off.
If not: Bent pin, corrosion, cracked adapter: replace the adapter (cheap) or have the frame port harness fixed. Verdict: bike.
7. Is the display showing a battery error?
Fit the pack, switch on. Note any E0xx code on the display or in the E-Tube Ride app.
If OK: No error but no charge: BMS charge path. Verdict: battery, dealer.
If not: E010 (system error), E011 (battery communication) or E013 (battery firmware) all point at the pack. Verdict: battery; some clear with a firmware update via E-Tube.
Fit the pack, switch on. Note any E0xx code on the display or in the E-Tube Ride app.
If OK: No error but no charge: BMS charge path. Verdict: battery, dealer.
If not: E010 (system error), E011 (battery communication) or E013 (battery firmware) all point at the pack. Verdict: battery; some clear with a firmware update via E-Tube.
8. Is charging just slow rather than absent?
EC-E6000 delivers about 1.8 A: a 630 Wh BT-E8036 takes over six hours from empty. Note the time the first battery LED took to appear.
If OK: LEDs climb, only slowly: nothing is wrong. Cold garages add an hour.
If not: No LED after 30 minutes: back to step 5.
EC-E6000 delivers about 1.8 A: a 630 Wh BT-E8036 takes over six hours from empty. Note the time the first battery LED took to appear.
If OK: LEDs climb, only slowly: nothing is wrong. Cold garages add an hour.
If not: No LED after 30 minutes: back to step 5.
What you now know for sure
- Charger failed: Fast blink or no output on a pack that charges from another Shimano charger. → Replace with the matching model. EC-E6002 replaces EC-E6000 on all round-connector packs; EC-E8004 only for the flat-plug packs.
- Battery locked or faulty: Pack refuses charge on a good charger, or shows E010/E011/E013. → Dealer with E-Tube reads cell balance, error log and can attempt a firmware update. Ask for the report before buying a new pack.
- Charging adapter or frame port: Pack charges off the bike, not on it. → New SM-BTE60 adapter (E6000 series) or frame port harness repair (E8000 series). Cheapest verdict of the three.
- Temperature pause: Slow blink on the charger; the pack is too cold or too warm. → Two hours at room temperature. Nothing to repair.
Manuals and video
Videos found on YouTube and checked automatically; they are other people's work, not ours.
- Shimano STEPS won't charge? Check this first! Tigard_Stripes
- Shimano Di2 Battery Charging and How to Check Di2 Battery Level #shorts #shimano #di2 Dave's Cycling
- Honest Review of replacement SHIMANO Di2 Charger Saving Benjamins
Frequently asked
Can I charge a Shimano battery with a generic 36 V charger?
No. The pack expects a data handshake from the Shimano charger before it opens the charge path; a generic charger just shows green. Forcing current in with the wrong plug can damage the connector. Use EC-E6000/E6002/E8004 only.
The Shimano charger LED blinks slowly. Is it broken?
A slow one-per-second blink is the temperature pause. The pack is too cold (below about 0 degrees C) or too warm (above about 40). Bring it indoors and it resumes on its own.
Which Shimano charger fits which battery?
EC-E6000 and EC-E6002 fit the round 2-pin charge socket on BT-E6000, E6001, E6010, E8010 and E8014. EC-E8004 fits the flat plug on BT-E8020, E8035 and E8036. The E8004 also charges the older packs through an adapter cable, but not the other way round.
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.