[Clearpath Husy A200] faulty diode

Controllers
1

Dear Support Team,

The diode labeled D1 (see image below) on the main PCB seems to be faulty:

20250610_120802
20250610_1208021920×3950 457 KB

This diode is connected to the blue connector shown here:

20250611_100408
20250611_1004081920×933 64.7 KB

Could you please provide the part number (if available) and explain the function of this diode in this context? Currently, we are able to start the Husky and receive the ROS2 topics, but the communication indicator does not turn green, and we are unable to drive the Husky.

Thanks in advance!

2

@Azib could you please check.

Also if the indicator is not showing then the cable might’ve come loose of the Husky to the main board which is a common issue.

Also for a sanity check please ensure the emergency switch is released by twisting it and and ensure the key position is in unlock position.

3

Dear Salman,
we have already reviewed the points you mentioned above. Could you please provide the part number of the diode, if available?

Thanks.

4

Hi,
Could you please check if D1 and the solder joint are connected (see the red line below), assuming you have a similar board available?
We can’t detect any connection. The trace may be damaged or burnt.

20250612_131905
20250612_1319051920×3950 406 KB

Thanks!

5

Dear @SAL

can you please check if all the fuses in the power board are still functional and not blown. They are located under the power input port

6

Hi @Azib

Yes, we have checked all the fuses, and they are all intact. All the LEDs are on, and the heartbeat indicator is working fine. The topics are being displayed, and all connected devices (USB hub, LiDAR, etc.) are functioning. However, the COMM indicator doesn’t turn green, and the Husky doesn’t drive.

Thanks!

7

@SAL can you check if the platform service is running?

sudo service clearpath-platform status

As well as

journalctl -u clearpath-platform -n 50
8

@Sohail
OK, here are the outputs from the command lines you sent us:

sudo service clearpath-platform status

platform_status
platform_status1846×661 192 KB

and journalctl -u clearpath-platform -n 50

journalctl
journalctl1848×947 364 KB

We also checked the /a200_0930/platform/mcu/status/power. It returns the following output. As you can see, battery_connected is set to 0.

topic_mcu_status_power
topic_mcu_status_power696×371 28.2 KB

f you have a circuit diagram or the physical board, it would be helpful if you could check whether there is a connection between the diode and the connector (see the red line below). The forward voltage drop across the diode is approximately 0.57 V (is it correct?).

image

Thanks!

9

Hi, unfortunately, for that, you have to contact Clearpath. However, from the service, everything should be working. @Azib could you give SAL clearpaths email for support?

10

@SAL Clearpath replied as following:

  • "The D1 diode is a part of the part sense circuit, if it has failed, it could be an indication that a reverse voltage was applied to the battery connector. Would it be possible to follow up with the client on the circumstances leading up to the diode failing?

    • Ensure that they did not inadvertently connect the battery in the wrong orientation.
    • Ensure that the battery is healthy (i.e. good state of charge, can supply current normally, etc.)

  • In the image it appears that the trace to the battery sense lug has become exposed. Has this client replaced or worked on this MCU in the past?

  • The part number for a replacement D1 diode is SMCJ5.0A (Example source: SMCJ5.0A Littelfuse Inc. | Circuit Protection | DigiKey) Bear in mind that if you proceed with this the warranty on the MCU board, if it is still valid at this point will be void."

11

Dear Support Team,

Thank you for your excellent support.

As expected, connecting the trace to the battery sense lug resolved the issue. However, we are still unsure why a reverse voltage was applied to the battery connector in the first place.

Please note that the Husky has been stored indoors in a dry environment throughout.