Troubleshooting Procedures

This guide provides step-by-step procedures to troubleshoot ASI BAC motor controllers and facilitate warranty claims. It covers low power controllers (BAC355, BAC555, BAC855) and is generalized for various applications.

Required Tools

Before beginning troubleshooting, gather the following equipment:

Wiring Reference

Control Connector Pinout

Step 1: Visual Inspection

Before electrical testing, perform a thorough visual inspection.

Record Controller Information

Document the following from the controller label:

• Model Number
• Part Number
• Hardware Number
• Firmware Number
• Parameter File Number
• Revision
• Serial Number
• Country of Origin

Document the Issue

Record the nature of the issue with as much detail as possible:

• When does the problem occur?
• Is it intermittent or constant?
• What were the conditions when it started?
• Have any recent changes been made?

Physical Inspection

Examine the controller thoroughly for:

• Cracks in the housing
• Burns or discoloration
• Damage to connectors
• LED indicator condition
• Any other visible defects

Step 2: Short Circuit Check

Use the resistance function on your multimeter to verify no internal shorts exist.

Resistance Tests

Perform these measurements and record results:

Capacitance Test (Optional)

If your multimeter has capacitance function:

• Measure between Battery+ and Battery- terminals
• Record the capacitance value

Only proceed if all resistance tests pass.

Step 3: Power-Up Test

Connect and power the controller using a current-limited supply.

Step 4: Communication Test

Establish communication with the controller.

TTL Connection

CAN Connection

If using CAN-compatible controller:

1. Use baud rate 250kbps and address 42 (ASI defaults)
2. Connect PEAK CAN dongle through USB isolator
3. Use appropriate settings if previously configured differently

Bluetooth Connection (if applicable)

1. Verify controller part number includes "BT"
2. Enable Bluetooth on mobile device
3. Look for "e-Bike" or "ASI devices" in BACDoor Mobile
4. Place phone close to controller and refresh

Unresponsive Controller Recovery

If the controller doesn't respond (LED off, no communication):

If still unresponsive, stop testing - controller requires return for service.

Step 5: Record Controller Status

Once connected, document the controller state.

Version Information

Record from BACDoor:

• Firmware version
• Build version
• Variant
• Bootloader version
• OTP Serial number

Save Parameters

Use Save to File (not Save to File 512 or 256) to capture all parameters.

Check Fault Status

1. If status indicator is red, hover cursor to read fault
2. Navigate to Features/Faults tab
3. Check Faults, Faults2, Warnings, Warnings2
4. Record any bits set to 1

Record OTP Serial Numbers

Navigate to Controller Debug/OPT/CRC/Version tab and record:

• OTP serial number 0
• OTP serial number 1

Step 6: Peripheral Verification

Test all peripheral outputs and inputs.

Voltage Outputs

Measure these outputs with multimeter:

Floating Input Voltages

Measure floating voltages (not connected to anything):

Digital Input Testing

In BACDoor, observe the digital inputs bit vector:

Bits should toggle to 1 when connected to ground.

Analog Input Testing

In BACDoor, verify analog inputs respond:

Switchable Output Testing

Test the 6V switchable output:

1. In BACDoor, write 1 to Remote digital commands bit 1
2. Measure 6V output with multimeter
3. Write 0 to turn off
4. Verify output turns off

Low-Side Switch Testing

Test HDQ low-side switch:

1. Write 1 to Remote digital commands bit 9
2. Measure resistance between HDQ pin and ground (should be low)
3. Write 0 to turn off
4. Resistance should return to high

Step 7: CAN Bus Testing

For CAN-compatible controllers, verify CAN communication.

Termination Check

1. Ensure both ends of CAN bus have 120Ω termination resistors
2. Measure resistance between CAN-H and CAN-L (disconnected from devices)
3. Expected: ~60Ω (two 120Ω in parallel)

Use Communications Configuration Vector bit 12 to enable software termination if needed.

TPDO Configuration

Ensure TPDOs are configured to send periodic messages:

Navigate to CAN TPDO1,2 tab and configure:

• TPDO enabled
• Appropriate transmission interval
• Save to flash

PCAN Viewer Test

1. Connect PEAK CAN dongle (with USB isolator)
2. Open PCAN Viewer
3. Set baud rate to match controller configuration
4. Record:
   • Address showing data
   • Data content

No Data Troubleshooting

If no data appears:

• Verify termination resistor configuration
• Check TPDO setup
• Verify baud rate matches

Step 8: POST Testing

Power-On Self Test verifies phase hardware.

Record Current Sensor Offsets

In BACDoor, record:

• Phase A current sensor offset
• Phase C current sensor offset

Record Phase Voltages and Currents

Record displayed values for:

• Phase U/A, V/B, W/C voltages
• Phase U/A, V/B, W/C currents

POST Parameters

Start polling these parameters:

Run POST Test

1. Set Motor discover mode to 1 to run POST
2. Record all POST parameter values
3. Record any faults that arise

Common Issues and Solutions

Controller Won't Power On

Communication Failures

Fault Codes Present

See Protection Systems for fault code interpretation and solutions.

Warranty Claim Preparation

When submitting a warranty claim, include:

1. All recorded controller information
2. Description of the issue
3. Test results from each step
4. Saved parameter file
5. Photos of any visible damage
6. Flash code pattern observed

Next Steps

• Review Protection Systems for fault code meanings
• Check Technical Q&A for common questions
• Contact ASI support at support@acceleratedsystems.com with diagnostic data