View Full Version : stupid board question....

2014.01.20, 06:13 PM
Anyone ever had the magic smoke come out of the steering motor area on an ASF (mr03) board?

Swapped out a motor and suddenly got a bit of a "poof" now no steering motor no matter what i do.

anyone with history and some advice?

2014.01.20, 07:00 PM
You could've blown the steering fet. Try changing that out if your steering motor is still good.

2014.01.20, 07:04 PM
Yep, time for new steering fets - be aware they are tiny on an mr03 board! Also check for shorts before applying power with the new fets installed.

2014.01.20, 07:33 PM
weird....they look fine.:confused:

anyhow....you got any skill with these tiny ones Steve? As you know my soldering abilities are a bit lax and these tiny ones would just be a lesson in failure for me.

LMK if anyone (Grant?) could pass this board off to you and i'll get a 4562 upgrade and steering fets done if you can.

I'll make it worth your while.;)

2014.01.20, 09:19 PM
Yeah, I can swap them out. We will need to find replacements, I believe I have seen the part number listed here before. If you come across it let me know, I can probably order some in the next week or two.

edit - found it listed on the forum, the steering fets are Rohm QS6M4
In stock at both Digikey and Mouser so I can get them.

2014.01.20, 09:29 PM
Cool. I'll bring it Sunday and pass it off to Grant.


2014.01.21, 12:54 PM
this same thing happened to one of our guys last week. we replace the fet off another board that was bad, steering seems to work but when it's put in place in the car is locks to one side or the other? Not sure what is going on with it.

2014.01.30, 02:45 PM
Fets are now in stock, just need the board.

2014.01.30, 06:46 PM
sweet...get Grant over to run some laps!

really appreciate your help, Steve.;)

2014.01.31, 08:23 PM
The patient is now in the shop.

2014.02.01, 01:16 PM
With no other updates I assume the patient made it through with flying colors?

Pretty stoked that I'll get this back in time for another 03 chassis blank...do you think 4 MR03's is too many?:D

2014.02.01, 03:41 PM
In typical Canadian medical system tradition your board is still waiting for a bed and for an OR to open up.
I'll probably work on it this evening.

2014.02.02, 10:51 PM
The patient survived the procedure with flying colors. There are now a total of 16 new fets(8 individual packages) installed in the MR03 board. It not only drives forward and reverse it has steering!

2014.12.30, 09:32 AM
Are there marked improvements on steering when replacing the steering servo motor/fets?