Omori boost gauge dimmer help needed.

Off-topic Chatter
1

I have a eBay voucher to use and I have been looking at Omori boost gauges for some time so I thought I’d spend some money and get one.

The only concern is that they are too bright and j-spec tuning (who sell the gauges) no longer sell the “dimming kit”.

Being backlit by LED you cant use the same dimming wires from your dash lights that use bulbs.

This is what it can look like at night before the dimming kit:

I found a post on a MR2 forum using Omori boost gauges and they used a 12v DC dimmer for LED’s it uses PWM (pulse width modulation) rather than regulating the voltage which would cause the LED to shut off , the dimmer switch and video are below.

Is this pretty straight forward or am I missing something?

Is there better 12V PWM dimmers I can buy that are more suited to be used in a car?

Thanks.

2

This is my amateur unqualified opinion:

When I was looking at auto 12v stuff I found these

You should be limiting the current with current regulation rather than PWM for this application. PWM can cause that jittery effect with movement and it won’t look smooth. I’m not sure what frequency it operates at or whether it even will be noticeable on the gauge, but if it is, then you’re gonna be pretty annoyed by it.

The one I linked regulates current so it’ll be dimmer but won’t jitter. It’s not designed for constant dimming adjustment though. The adjustor is rated for 100 or so adjustments which means you are meant to really just figure out what works for day and night and just leave it there. That’s how my boots gauge works anyway and I live with it.

I had an AW11 SC back in the day. Way too tail heavy but great bottom end.

3

Thanks for the info.

Thats interesting, I really didn’t think about the PWM affecting appearance of the needle when it moves.

I have my instrument panel illumination pretty low to cut down on glare and to preserve my vision on the dark roads etc, so I’d just set it and leave it too.

$6.95 international shipping is pretty reasonable but are you 100% sure it would work? I don’t understand electronic terms very well but from what I have read is they (Omori gauges) are very sensitive to voltages and will cut out completely with much less than 12v so the PWM controller is needed. If the current is lowered does the voltage stay the same?

It looks relatively easy to wire up and I’d prefer that one over the huge white box if its going to work.

I actually have a 2002 WRX but just saw the info about it on the MR2 forum when I was searching for answers.

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Honestly could’nt tell you if it’s going to work for your specific application. Send the seller an email he’s good with responses.

5

Subscribed for some MR2 love. The gauge is on my to-do list when I’m back in the country.

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@ aoue, I sent him a email, thanks.

@ Tech2, I’ll post my my install and results (even though its in a different car), it might help you out with yours.

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Thanks, I’ll appreciate that.

I like the idea of being able to adjust on the fly, but I see what you mean about that big unsightly box. Ideally I’d like to have the potentiometer within reach. Not sure where the white box would go.

8

you live in paradise!

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That’s my brothers back yard, he has a really nice place. I rent a tiny single room apartment about 5 mins from there.

But most of the time I spend at my brothers house either working on cars or in that shed (which is kind of set up as my office).

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I got a reply from LED Supply, he said the engineer told him that the boost gauge would already have its own driver so I wouldn’t be able to use one of their dimming drivers.

However he said dimming via PWM is the correct way to do it so it looks like I’ll have use the $3 eBay PWM dimmer.

It looks like the eBay PWM dimmer is easy to disassemble and I could rig something up out of sight and perhaps in a smaller case.

I found pics of someone with one taken apart and mounted the knob on the outside of a tray, but I think I might just grab a little black box from the electronics shop and fix up something under the dash.