MR2 Owners Club Forum banner

DIY $13 Wideband Display

5673 Views 13 Replies 9 Participants Last post by  Mr2_Dr3w
Partially due to not having a good spot to mount another round gauge (don't want an A-pillar pod or to loose my vents) and partially due to not wanting to pay the extra 40-50 bucks for one, I decided to try something different for my wideband display.

I picked up one of these on ebay for $13 with free shipping (from Sure Electronics ebay store).

Using the included USB-Serial converter I programed it to convert the 0-2v signal from the LC1 to 7.35-22.39 (the full range of the LC1). I had some trouble getting this to work correctly at first, it kept giving me an out of range error, but I discovered that if you moved the decimal point to the left a couple of places in your formula it would work just fine.

At this point you have a display that will give you 0735 at the low end and 2239 at the high end, with no decimal point. As far as I could tell there was no way to get a decimal to display using software. However, if you are a little handy with a soldering iron you can get around that.

For some reason the meter has all 4 decimal points wired together in the circuit board. To get around that, I cut the traces on the front and back where circled, and then to power the second decimal (the one we want) I soldered a 680ohm resistor between the two pins marked with dots to provide power to the decimal.

A quick coat of black paint on the housing, and a little dremel action on the stereo pocket (pocket isn't quite tall enough for the display, removing the lip at the bottom solves that). I wired the 12v supply for the meter into my stereo, grounded both the meter grounds to a bolt in the trunk (where I grounded my LC1) and wired the meter input to one of the LC1 outputs. The end result looks like this:

All in all, I'm happy with it. Its a little tough to read in direct sunlight, but I have yet to meet a digital display that isn't. In all other conditions the auto dimming feature of the display works quite well, keeping it from getting too bright at night but keeping it easily readable in daylight. I may try to make a little sheet metal hood for it to solve the sunlight issue.
See less See more
1 - 14 of 14 Posts

How accurate is it and what wideband sensor did you use? Thanks
From the pics, it looks like two of these could fill up a single DIN no problem? With as many alternators i've went through in the past few years (hopefully a non-issue now that I sprung for a Denso reman instead of the generic crap) I'd definitely hook one up to a switched power supply and a fuel pressure gauge :)
The wideband controller is an Innovate LC1 (I thought I mentioned that), which uses a bosch sensor. I don't really have a good way to test its accuracy, but it seems to read pretty much the same as what I get if I hook my computer to the LC1 and read it directly. The LC1 is supposed to be very accurate from what I have read.

There is definetly enough space there for a second display, with room to spare, but I don't quite get why you would want two of them.
Alex W said:
I don't quite get why you would want two of them.
Can one of them toggle between multiple sensors?
Great job by the way!
I'm assuming you changed the "5.00" to "2.00" volt at 22.39 afr, correct me if I misinterpreted you...
See less See more
Yeah, the display only reads from 0-2v, so I changed the output on the LC1 to 0-2v. There is also a display available that reads from 0-10v, and I thought about doing that and only using half of its full scale. I don't think it would really make much difference either way.

I suppose you could pretty easily put in a switch to go from one input to the other if you wanted, if the other sensor was the same output (another wideband). If you wanted to read something else you could definitely put in a second display though.
Does this new lcd display if there is an error going on with the wideband gauge. I remember seeing my friends innovate wide band showing an error code and when we looked up the error code it was telling us how his wideband o2 needed to be replaced.
The innovate can be programed to output a given voltage for an error condition, and also for warmup. I have mine set to 0v, so my display shows 7.35 AFR if there is an error. Its not a code, but its a pretty clear sign that something isn't right.
Great stuff!!!

As far as the LC1, its one of the better widebands out there for accuracy. We looked into the LC1 wideband, and found that as long as you follow the install directions and perform the calibration correctly, then you'll have a great data.
1991 MR2 Turbo said:
what program did you use for this
Software can be downloaded from the instruction pdf for programming the display. Software to program an innovate wideband is available on their site.

Nothing to crazy, everything is easily found and easy to use.
1 - 14 of 14 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.