Anybody able to read Japanese handy... - Page 1
Forum section: electronics / general

author: sleemanj
author_rank: Super Contributor
timestamp: February 05, 2015, 06:54:27 am
content: So to cut a long story short, I'm trying to work out if this page describes a normally open or normally closed thermoswitch. It's from the service manual from my vehicle.Long story is that, the fan in my little japanese kei class truck is on permanently, has been since I got it, I assumed it was the thermoswitch failed, it was "failed" short, so, first I got a thermoswitch sent from a Japan seller on Yahoo.jp, it was supposed to be for the correct model etc, switch arrived, exactly the one which was advertised, but, completely the wrong size (incorrect thread, way too big ...) to replace the one that's in it, it is however a normally open switch as I'd expected.So time passes because I'm lazy, but eventually I track down the numbers on the one that is installed, and I find a seller on Aliexpress with them, and get two (because they only sold them in pairs!) sent out, they are the correct size and appear to function, except when I tested them - these are normally closed. I do some more digging, and indeed, that model of switch is supposed to be.But the fan turns on when the switch is closed, and it's normally closed.... so, something's not right here somewhere (and maybe I'm lucky it never got hot enough to open the thermoswitch and turn the fan OFF).

author: tautech
author_rank: Super Contributor
timestamp: February 05, 2015, 07:23:40 am
content: If its in a pdf use Google translate.Or do a proper bodge and use another relay with NO & NC terminals to reverse the thermoswitch logicto that the vehicle wiring understands.Or possibly the existing fan relay is thewrongone and should be a NC(if your explanation is correct)

author: sleemanj
author_rank: Super Contributor
timestamp: February 05, 2015, 07:39:44 am
content: Quote from: tautech on February 05, 2015, 07:23:40 amYeah the machine OCR and translation I got are not entirely clear (poor image and,well machine translation). I'm fairly certain that it is supposed to be normally open.Quotewas the best I could get, which is probably two separate ranges, and I'm guessing that no conduction is open,and "more conduction" is closed.I've considered just bodging it with a suitable relay and probably will (since I now seem to have 3 somewhat expensive new thermoswitches I might as well try and use one), but I think I'll install a temperature gauge and a fan-running indicator led first just so I can keep an eye on it.As for an incorrect installed relay... it doesn't have one, fan appears directly connected through the thermoswitch (3.something amps worth).

author: dexters_lab
author_rank: Unknown
timestamp: February 05, 2015, 09:02:22 am
content: temperature switches are normally open and go closed at the set temperaturethis means you can normally unplug the connector with the engine running and the fan should operatei'm guessing this is the radiator fan switch?

author: coppice
author_rank: Super Contributor
timestamp: February 05, 2015, 09:06:46 am
content: Standard conditionsBelow 87+-3 degrees C No conductionAbove 93+-3 degrees C ConductionCold places:Below 93+-3 degrees C No conductionAbove 98+-3 degrees C Conduction

author: sleemanj
author_rank: Super Contributor
timestamp: February 05, 2015, 09:10:40 am
content: Quote from: dexters_lab on February 05, 2015, 09:02:22 amThis is what's fitted, it's the opposite (normally closed, opens at temperature).QuoteYes.But we are not talking about an ordinary car here :-/

author: sleemanj
author_rank: Super Contributor
timestamp: February 05, 2015, 09:13:13 am
content: Quote from: coppice on February 05, 2015, 09:06:46 amThanks. So yeah, that confirms, the one which is in it, is inverted for some reason, must have been replaced by some numpty in the past and they just figured it was OK since the fan was running all the time anyway.

author: Falcon69
author_rank: Super Contributor
timestamp: February 05, 2015, 09:14:03 am
content: ISn't that the car that Erkl drives in Family Matters TV show back in the early 90s?

author: sleemanj
author_rank: Super Contributor
timestamp: February 05, 2015, 09:21:12 am
content: Quote from: Falcon69 on February 05, 2015, 09:14:03 amNo, you're thinking of an Isetta (which I would quite like to own one of ;-)), this is a Daihatsu Midget II

author: dexters_lab
author_rank: Unknown
timestamp: February 05, 2015, 09:41:14 am
content: Quote from: sleemanj on February 05, 2015, 09:21:12 amKei cars are great, but too small and underpowered for the UK roads.