TB Gallant
TVWBB Member
Hey guys,
So have my old v4.0 board working pretty good except the blower doesn't work. I tested it by hooking it up direct to 12V and works good so must be something on the HM side. Some things I've tested so far:
- checked the various 5V and 3.3V on the HM board using an old diagram I found. Some of the 3.3V locations are a bit 'low' in voltage (2.9V and 2.8V on RX and TX I think) but otherwise all good.
- checked the +12V pin on the blower J4 and it is 12.5V
- when I first power up the HM/Pi (Zero W) the output on the blower starts high (closer to 12V) but then consistently drops to essentially nothing, 0.16V or so. This must be a clue but I'm not electrically intelligent enough to know what it tells me
- the center pin of the FDP7030BL does seem to 'pulse' to ground (check ohms between ground and center pin, goes from 1 (infinite) to some other value, back and forth cycling)
I know that this old v4.0 setup pulses the blower ground, but even with the fan output stating 100% the same symptoms happen above.
Appreciate any help someone may be able to offer for this ancient board.
Cheers,
Tim
So have my old v4.0 board working pretty good except the blower doesn't work. I tested it by hooking it up direct to 12V and works good so must be something on the HM side. Some things I've tested so far:
- checked the various 5V and 3.3V on the HM board using an old diagram I found. Some of the 3.3V locations are a bit 'low' in voltage (2.9V and 2.8V on RX and TX I think) but otherwise all good.
- checked the +12V pin on the blower J4 and it is 12.5V
- when I first power up the HM/Pi (Zero W) the output on the blower starts high (closer to 12V) but then consistently drops to essentially nothing, 0.16V or so. This must be a clue but I'm not electrically intelligent enough to know what it tells me
- the center pin of the FDP7030BL does seem to 'pulse' to ground (check ohms between ground and center pin, goes from 1 (infinite) to some other value, back and forth cycling)
I know that this old v4.0 setup pulses the blower ground, but even with the fan output stating 100% the same symptoms happen above.
Appreciate any help someone may be able to offer for this ancient board.
Cheers,
Tim