KIMI 3 - 1984 Series 3

[rotarypower]

https://www.carbuilder.com/uk/relays#/p ... orderBy=15

There are various flasher relays that can do the job. You might need to change the wiring around a little bit, I think we'll find more and more that we need to start 'modernising' some of the electrics on our cars as the stock of replacement parts gets thin on the ground.

[Casey]

Thanks for that

I've had a closer look at what is in that module and realise it handles all the signalling and warning lights (dash and F/R), dimmer for dash lights, buzzer warnings and goodness knows what else! There is quite a bit of discrete electronic circuitry inside. The Mazda wiring diagrams are tough to piece together as the numerous functions in there are split across several page. But, I'm having fun puzzling it out how it all works

If anyone has a spare one to donate (or sell), working or not, I'd love to get one to take apart and see what I can do to modernise/upgrade it. I can also look at possible upgrades, like an adjustable tacho buzzer sound, etc!

[KiwiDave]

I will have a look for the one I changed out, Malcolm. If I can find it, I'll send it over.

[Casey]

Thanks Dave, that would be brilliant.

It was a lovely day here today, with dry roads, so took my car out for a 25 mile run. The noise was there throughout

I hope I have a decent enough recording to pop up later, but I'm 90% certain you are correct, it's that module where the noise is coming from

[danny]

Try to open that box and have a good look at the circuit board. Sometimes it is not possible to see by the naked eye, but there may be a bad contact Just re-soldering the board may solve the problem.

[KiwiDave]

Brilliant Dave, that looks worth investigating.

If it turns out to be that, I might even see if the function can be designed/replicated using some more modern electronic components.

I've had a good look Malcolm but I haven't managed to find it yet. As is the way with these things, it will turn up when I'm not looking.

[Casey]

I finally got around to removing the "CPU" from KIMI 3 - more accurately described as the hazard and flasher module

It would appear there are several iterations of the innards, as I have a version marked "E", whereas Dave's picture a few pots up shows a "D". The first thing to note is that the "D" version clearly has a "buzzer/speaker" visible through the slotted aperture, whereas my "E" version doesn't have one!

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The circuit diagram in the Mazda documentation is as much use as a chocolate teapot. However, a quick visual examination showed this capacitor leg disconnected! You can see the location in the larger picture above, just below the "Taiko" relay. Goodness knows how that got like that in the plastic casing.

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I tried to doe some reverse engineering of the circuitry, which is a bit of a nightmare, especially as the Mazda wiring diagrams don't seem to match this "E" version module. Plus, I think a lot of the missing circuitry on the board relates to "seatbelt not fastened" and other warnings that are not present on the UK spec model, so confusing matters. I'm hoping that putting that capacitor back in circuit will fix the annoying buzzing. Without it, by looking at the circuit, I think one of the relays may be chattering and causing the noise. Then again, there might be something else going on.

I haven't worked out why there is a need for 3 relays on the board (2 electromagnetic ones and a reed relay).

I'll resolder the cap in place and put the module back and see what happens. If it's not that, more circuit head scratching will be required

[Casey]

My confidence was unfounded - the noise is still there!

Only when the engine is running and it disappeared fairly quickly, before the choke released. Sometimes it stays for 40 miles or more. I still can't be certain of the source of the noise. It's around the drivers knee area, but could be from the other side of the bulkhead, or the dashboard. I'll live with it for now. as it doesn't seem to be affecting anything.

But, on the test drive, I tried to wash the windscreen and ............nothing happened

I knew there was water in the washer bottle, so concluded an electrical issue. Got back, checked the pump motor was getting 12 volts - OK. Checked the motor coil resistance and it's open circuit

I love these cars keeps me on my toes.

I'll see if I can get the motor apart and fix. Otherwise, has anyone got a washer bottle and motor for sale? The bottle has a small leak when the metal fixing bracket has worn through the plastic bottle. I've plugged it, but I doubt it will last long.

Does anyone know if the pump motor on the rear windscreen is the same. From memory, I think it is. If so, that's another temporary fix option, if the motor turns out to be u/s.

[ian65]

the rear washer motor is the same Malcolm and they are usually in better condition as they are inside the car and have little use.
On the subject of this mystery noise, are you sure it isn't coming from the flap mech in the air filter housing? Mine makes a noise from there until it warms up.

[Casey]

Thanks for confirming Ian - I was hoping that was a potential Plan B

The good news is, I've just come in from the shed and the motor is back working. Just spun it by hand to free things up. It starts and stops every time, so maybe some use left in it for a while yet.

If it fails again, I'll dismantle it and take a look inside before Plan B