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Troubleshooting

Dash Display

How to use the instrument cluster to extract basic diagnostics from the bike, and also understand when and how it's malfunctioning.

Entire Display Flashes

If the dash display in its entirety is flashing after keying the bike on, this indicates an onboard charger self-test failure.

Key the bike off and wait for a few seconds and retry, and it should clear.

No Backlight

Check your running lights and license plate lights, if those are also out then check the fusebox (see: seat removal).

If the fuse pops right away, there is a short circuit in the wiring harness (as happened to a MY2016 DSR pinched wiring harness (or mouse nest!) to the license plate lights).

Disconnect the tail light module and the display module connectors; if the fuse still pops, try removing the tail and tracing the short circuit.

System Warning Sequences

This is a quick lookup for the red sequences flashed by the dash System Warning Indicator (a red triangle with an exclamation mark within it).

These are derived from the Official Owners Manual only for roadside reference and owner community annotations and links.

Overview

The red indicator light in the lower part of the display sometimes will flash a repeating sequence.

The Official Owners Manual lists what they mean, usually related to system startup.

Often enough, keying the bike off and on is the way to re-test.

System Warning Troubleshooting

  1. Toggle the Instrument Cluster's Display A to show Error Codes.
  2. Check the corresponding Error Codes

Some will be expected like kickstand down based on your context.

Focus on topical system errors related to the System Warning. 3. Attempt a basic reboot: 1. Charging: disconnect the external power source from the vehicle. 2. Key the bike off. 3. Wait several seconds or a minute in length depending on severity of the error. 4. Key the bike on, checking for a normal startup sequence, contactors closing, and no errors. 4. If the System Warning persists, and it is related to the BMS, perform a BMS Reset Procedure (soft and then hard reset). 5. If the System Warning persists, attempt to extract MBB logs.

Urgent/Roadside: Email logs to yourself, then decode using a log parser.

Non-Urgent or Important: Email logs to Zero. 6. If no clear resolution is at hand, contact Zero and/or your local dealer to schedule servicing.

# Blinks Description Cause Guidance
1 ············ Fast constantly Safety Override is Active
〃 · · · · · · · · Fast intermittently BMS Isolation Fault Check the BMS Isolation Fault section of the manual
Moisture and/or dirt are the most likely culprits.
〃 — = 1 long
- Charge Indicator blinking fast constantly
- or all blinking dash segments		 Charger Not Charging Probably a CAN Error
Unplug the bike and wait a minute to re-engage
〃 — 1 long Cutout switch engaged or Kickstand Switch Disabled Disengage the cutout switch and/or raise the kickstand.
2 ·· 2 short Self-test failed
3 ·   ··· 1 short, then 3 short High Throttle Disable The throttle signal is abnormally high or disconnected.
See Error Code 1: Check throttle rotation and connections.
4 ·   ···· 1 short, then 4 short Precharge Fail See Error Code 27.
5 ·   ····· 1 short, then 5 short Low Power Pack Disable See Error Code 7: Battery voltage is too low to operate
Charge slowly as soon as possible.
6 ··   · 2 short, then 1 short Contactor Error See Error Codes related to the Contactor.
7 ··   ·· 2 short, then 2 short Charger Error See Error Codes related to the Charger.
8 ··   ··· 2 short, then 3 short CAN Error
9 ··   ···· 2 short, then 4 short BMS Throttle Disable See Error Codes related to the Throttle.
10 ··   ····· 2 short, then 5 short Module Variance Too High See Error Code 32
11 ···   ··· 3 short, then 3 short Battery Temperature Sensor Fault See Error Code 18: A temperature sensor failure reduces safety; arrange a dealer visit.
Not urgent to fix unless other battery problems are apparent from logs/etc.
12 ····   · 4 short, then 1 short Contactor Welded See Error Code 26
13 ····   ··· 4 short, then 3 short Motor Controller Error See Error Codes related to the Controller.
14 ····   ···· 4 short, then 4 short Loopback Error See Error Code 35
Reconnect either an expected second battery module or Power Tank, if present.
Otherwise, reconnect the blanking plug.
15 ·····   · 5 short, then 1 short BMS Startup Error
16 ·····   ·· 5 short, then 2 short BMS Internal Disable
17 ·····   ··· 5 short, then 3 short BMS Internal Fault
18 ·····   ····· 5 short, then 5 short Miscellaneous Error

Error Codes

How to use the 2014+ instrument cluster to extract self-reported diagnostic codes from the bike.

Code Description (official) Manual Section Community Notes
0 No Error Almost abnormally normal!
1 High Throttle Throttle Likely throttle connection or potentiometer issue
2 Motor Temperature Warning Stage 1 Motor Near upper temperature limit; corresponds to blinking temperature light on the dash
3 Motor Temperature Warning Stage 2 Motor Reached upper temperature limit; might involve cutbacks or shutdown
4 Controller Temperature Warning Stage 1 Controller Near upper temperature limit; corresponds to blinking temperature light on the dash
5 Controller Temperature Warning Stage 2 Controller Reached upper temperature limit; might involve cutbacks or shutdown
6 BMS Throttle Enable Wire Error Throttle
7 Low Battery Voltage Contactor Limits Should only happen near/below 0% SoC or 84V dynamic pack voltage.
This can reset for a bit if the bike is powered off for a few minutes; charge ASAP.
8 High Battery Temperature Status Contactor Limits Can happen during a >4kW charge or while operating at speed in a hot environment.
Reduce battery load!
9 Low Battery Temperature Status Contactor Limits Can happen in winter storage; will prevent charging.
Use a space heater or bring the bike inside ASAP to prevent battery damage.
10 Battery Temperature Warning Stage 1 Contactor Limits
11 Battery Temperature Warning Stage 2 Contactor Limits
12 Reserve Partition Warning MBB
13 Reserve Switch Warning MBB
14 Safety Override Active MBB
15 Charger Attached But Not Charging Charger
16 CIB Contactor Compromised Contactor
17 Charger Error Charger
18 Battery Temperature Sensor Fault BMS
19 High Charge Current Contactor The contactor limit for charging was reached and the BMS opened the contactor.
Key the bike off and on to reset.
20 BMS Low Isolation BMS
21 Board Vpack Error BMS
22 Board Temperature Error MBB or BMS
23 Post Error MBB or BMS Power-On Self Test diagnostic result
24 Startup Error MBB or BMS Firmware boot diagnostic result
25 Contactor Open Warning Contactor This indicates the contactor is open.
This may be appropriate given what safety interlocks are in play.
26 Contactor Welded Error Contactor Only 2013 models have contactors that can realistically weld shut
The code indicates battery voltage on the power harness or bus when there shouldn't be any.
27 Precharge Error Precharge Indicates bus voltage didn't climb enough in the required time period to close the contactor safely.
Try keying the bike off and on again over a period of a few seconds to retry.
28 BMS Isolation Fault BMS Indicates any kind of ground indication as measured by various BMS circuits.
29 BMS Isolation Danger BMS Indicates a ground indication as measured by various BMS circuits.
The BMS protects itself by opening the contactor.
30 BMS CAN Error BMS CAN bus error to/from the BMS, as reported by the MBB?
31 SEVCON CAN Error Controller CAN bus error to/from the Sevcon controller, as reported by the MBB?
32 Module Variance Too High BMS Indicates that a module within the power pack is varying too much from its siblings (voltage? current?).
Provide a balancing charge with the onboard charger or any <0.4C charger.
33 SEVCON Error Turn Off Controller
34 Charge Error Turn Off Charger
35 Loopback Error Power Tank The connector for BMS1 (Power Tank or Power Pack Module) does not have a connected BMS or a blanking plug with loopback wiring installed.
36 Board 5V Error MBB MBB fault providing 5V micro-power (what's affected?)
37 Board 3.3V Error MBB MBB fault providing 3.3V micro-power
Pre-2017 OBD-II affected - otherwise just a type of sensing feedback
38 Idle Turn Off MBB The MBB timeout for detecting an idle control state has been activated, opening the contactor.
Reset by keying the bike off and on.
39 Throttle Out Of Range Disable Throttle The throttle's electric signal safeguard is active
40 BMS Throttle En Wire Disable Throttle The throttle's enable wire safeguard(?) is active
41 Low Battery Voltage Disable Contactor Limits The low battery voltage safeguard is active
42 High Battery Temperature Status Disable Contactor Limits The high battery temperature safeguard is active
43 Low Battery Temperature Status Disable Contactor Limits The low battery temperature safeguard is active
44 Kill Switch Disable MBB The kill switch safeguard is active
45 Kickstand Switch Disable MBB The kickstand switch safeguard is active
46 BMS Charger Connected Disable BMS The BMS checks whether the charger is connected, and this check failed.
47 MBB Charger Connected Disable MBB The MBB checks whether the charger is connected, and this check failed.
48 SEVCON Startup Disable Controller The Sevcon controller startup failed and the resulting safeguard is active.
49 Contactor Open Disable Contactor The contactor is open because of some safeguard (like 25 but not a normal indication).
Check other error codes and reset by keying the bike off and on.
Check logs later.
50 BMS Self-Test Error BMS The BMS runs a self-test to decide whether it's safe to operate, and it failed.
Check BMS logs immediately.
51 BMS Self-Test Warning BMS The BMS runs a self-test to decide whether it's safe to operate, and it succeeded but had a note.
Check BMS logs.
52 Reserve Partition Disable MBB The MBB reserve storage partition(?) safeguard is active.
53 BMS Internal Disable BMS A BMS internal check failed and the resulting safeguard is active.
54 Internal Disable Error MBB An MBB internal check failed and the resulting safeguard is active.
55 Internal Fault Error MBB Could be anything?
56 Monolith Not Connected BMS BMS#0 is just undetectable
(is this via CAN and voltage readings together?)
57 Module Did Not Connect BMS The contactor didn't close? Or something more basic about the BMS (main, power tank, or module) reporting the battery unready.
Probably use the onboard charger to fix.
58 BMS Sensor Warning BMS
59 BMS System Warning BMS
60 Bike Configuration MBB or BMS There may be an error in the bike configuration settings applied to the MBB and BMS.
Basically, they might have inconsistent model specifiers or battery size specifiers.
This has also been reported for incompatible firmware versions between the MBB and BMS.

Isolation Faults

Isolation Fault is jargon used on Zero Motorcycles systems to indicate a fault in some part of the system to isolate some HV electrical circuit from ground.

It can also mean the more specific condition where an attempt to locate the fault failed, an attempt to isolate the cause to a component or sub-circuit.

Indication

BMS isolation faults are indicated by a combination of codes 20, 28, and 29.

Meaning

  • On some part of the power system connected to the BMS at that moment, there is insufficient isolation (insulation) from ground.
  • This can include anything on the 116V power cabling "bus".
  • This is usually not a short, but can mean an imbalance that could compromise the bike's performance or safety.
  • If left unattended to, it could deteriorate to a serious problem; in-build protections should shut down the bike prior to damage but this itself would be unsafe happening while riding.
  • If the BMS reports a specific voltage in the logs with the isolation code, it means that a specific cell (the combined parallel cells at a particular level in the 28-cell series) has poor isolation to ground, roughly computable as "3.7V ⨉ N = logged voltage".

Possible Aggravating Conditions

  • Damp weather
  • Dust or mud ingress

Troubleshooting

  1. Disconnect anything attached to the Accessory Charging Port.
  2. If the condition clears, check the attached equipment (chargers and cabling) for grounding isolation.
  3. Key the bike off and on slowly, waiting after each transition to see whether the condition clears.
  4. If the error occurs without or before the contactor is shut, then the fault is within the battery and might be due to moisture or dust entering the front of the battery faceplate where the BMS is.
  5. If the error clears after opening the contactor, then the fault is likely downstream of the contactor, including the Accessory Charging Port signal pins, the Sevcon controller, Sevcon DC-DC 110V->12V converter, and the MBB and DC-DC connections.
  6. Check for moisture on the Accessory Charging Port signal pins and attempt to dry them as necessary.
  7. After everything dries out and/or the isolation fault has disappeared apply dielectric grease to all connections that would be vulnerable to water ingres (under the seat, 12V connectors, etc)

Controller Hypothesis

Reference: via DoctorBass

It might be the Sevcon Motor controller that is defective.

The codes are related to BMS isolation fault - as an interpretation of a voltage present relative to the frame.

  • A bad controller could have a single phase to the motor (M1, M2, M3 circuits) with a short to the heatsink.
  • Apparently Sevcon and Zero are aware of this potential problem.
  • The problem is apparently because the Kapton tape they use between MOSFET transistors' heatsink and the aluminum heatsink might be punctured and create intermittent low resistance contact to the controller chassis.

Warranty replacements have been reported.

Controller Isolation Diagnostic Procedure

A dealer should be able to do this easily.

  1. Key off the bike and wait 10 minutes for the system to fully discharge.
  2. Remove the seat.
  3. Uncover the top of the Sevcon controller.
  4. Verify all inputs and outputs of the Sevcon controller are de-energized (zero/low voltage).
  5. Disconnect the cables from the controller (M1, M2, and M3, the Ampseal 34-pin connector, and B+ and B- to be extra careful) and cover the leads for safety.
  6. Check for continuity between each phase (M1, M2, and M3 terminals) and the controller heatsink plate.
  7. If you get continuity (low resistance reading), then controller is defective.

2018-05-03, Doctorbass confirms:

I got these same errors couple month ago.. problem was the SR controller bad isolation from the phase output to the aluminum plate of his body. Controller replaced and that solved the problem.. no more 20 28 and 29 error code from now. The code talk about BMS but in fact the voltage level the controller bad electrical isolation create make the BMS to think it's the battery but in my case it was not.

Isolation Diagnostics test

  1. Access the MBB Console terminal
  2. Login via login
  3. Execute the isolation test command with the verbose flag: test isolation -v

Using Mobile App

See the Official Mobile Application article.

Diagnostics

Source: zeromanual.com/wiki/SDS_Platform/Unofficial_Service_Manual · Wayback capture of 2025-05-17 · wiki last edited 10 July 2020 00:05. Community-written content from the Unofficial Zero Manual, reproduced for preservation; not written or verified by OpenZero. Links to pages that were not mirrored go to the Wayback Machine.