Another AEM Uego and Megasquirt thread
 

Add me to the list of people with uego issues.

UEGO has 2 wideband outputs: serial TX and Analog+.

I found brain's instructions stating to use the white wire from uego to the blue input wire in the pigtail. I have the 12v and ground plugged in as well. When I try to turn the car on I get no wideband signal and the gauge doesn't power on. I double checked and everything is plugged in. I figured my connectors were messed up so I cut the wires and used new connectors, still nothing.

Trying to turn the car on and no signal. The ecu is set to Wideband AFR-default.
One note: the stock narrowband is still plugged in. There was nothing in the instructions that said it had to be cut out. I figured that you could just tell the ecu to disregard the stock sensor if you select the wideband, especially if it's coming in from this input. Am I wrong? Was I supposed to clip the stock connector and splice the wires in there or do both setups work?

I don't think this would explain why no power is being supplied to the gauges either right? Running a multimeter on continuity doesn't show any flow with the car in the on position.

What am I doing wrong?

:/

Snip from brain's instructions, my wiring, and the uego manual.

https://cimg3.ibsrv.net/gimg/www.mia...229ce66b77.png
https://cimg5.ibsrv.net/gimg/www.mia...177f90a9d1.jpg
https://cimg2.ibsrv.net/gimg/www.mia...ea79129b5e.png

Everything plugged in tight on the back of the gauge? Have you tried another power source?

Step one would be to get the gauge powered on. If it still doesn't turn on you may have a dead gauge.

im wondering if the brown is the sensor's ground and needs to be grounded in order to work.

you should be able to put a DMM on the white wire and read voltage.

Perhaps it's because it's not grounded as brain said below. The plugs are clipped in.

I bought the gauge used on here a few months ago I hope it wasn't a dud...

Should I splice the brown wire in with the other gauge for ground? I'll try the dmm as well.

I had to cut out your connector because I wasn't sure if that was the issue and I ran out of wiring space. I'll have to extend the wires a bit to keep at this

Perhaps it's because it's not grounded as brain said below. The plugs are clipped in.

I bought the gauge used on here a few months ago I hope it wasn't a dud...

Should I splice the brown wire in with the other gauge for ground? I'll try the dmm as well.

I had to cut out your connector because I wasn't sure if that was the issue and I ran out of wiring space. I'll have to extend the wires a bit to keep at this. Womp.

power on and put it to any metal on the chasis for now, and test the white wire for 0-5v with and without.

So just check it with continuity with the other ground on metal? Got it.
I can check when I get home tomorrow night.

I'm still so confused why the gauge isn't powering on.

if the MS is powered up, then you should have 12v at that wire as well...all fed off same source.

looking at that diagram, i would have wired it the same as you did.

Sounds like it's time to bench-test the Gauge. It should at least power up with just the red wire hooked up to 12V and the black to gnd. Stop by tomorrow and we'll see what we can do.

Womp. I didn't drive it here. It's not running right now. I'm in the subie. Looking forward to getting a ride along!

Dang. Ride-along is still on though :)

I'm trying to be responsible about this build dagnabbit!

Bad news brain.

https://cimg8.ibsrv.net/gimg/www.mia...a7cda7c2da.jpg

Gauge glowed bright red when I touched the wires to the battery terminals.

Thanks again for your advice Stefan!

To elaborate a bit (as Stefan suggested).

Stefan talked me through the tests to figure out where the issue was originating.

First we checked the gauge. I held the red/black wires up to the car battery and it flashed on. Okay, so gauge is working. Of note: I did not kill myself. Stefan says that would be hard to do. He doesn't know me well yet though. I am capable of impressive things.

Second, I decided to check if the MS was actually supplying power. First, I ensured that I was on the right setting by using the MM on the battery to ensure it was supplying 12V. It was.The harnesses are plugged in tight, so no issue there. I put in butt connectors to the power and ground wires and shoved the MM wires into the other end. Turned the key to the 'on' position. Andddd no power.

So it appears that the megasquirt isn't supplying 12V power. I don't know if I can trust the signal and ground wires either at this point, otherwise I'd try powering the gauge/wideband by splicing into the radio and seeing if the megasquirt gets a signal from the wideband at all.

Wait - you were supplying power via the MS? Is that a common thing? I suplied power to mine via a switched 12v signal. In my case it is a relay driven off the fuel pump signal and powered by a run directly from the battery to behind the dash.

I don't make the rules, I just follow them.

Bought a braineack unit, blindly following his directions!

Waiting to hear what Brain has to say... Without knowing how the MS is supplying power (through what fuses, relays, and output pins on the unit itself) I can't make any more comments or speculations.

the MS doesn't supply the power, it's SUPPOSED to come from the white/red oe harness -- the same source that powers the MS.

RTC, email me and we'll figure out why youre not getting 12v there.

Yeah MS is getting power because I've connected the laptop to it. It doesn't have any lights so I can't tell if there's a status it's displaying via the light.

Same as PayPal email I'm guessing?

yes

Wouldn't the simple fix just to be running the red wire to a switched 12v source with an inline fuse? Doesn't matter where the gauge is powered from. Realistically you're probably just going to use those three wires ever. Give that red some power, ground that black one at the MS common ground, and then feed the MS WB input that white wire. Or am I suddenly a crazy person?

You're not wrong, but the issue is that the MS was behaving unexpectedly given how it was wired.

Brain and I did some troubleshooting and the unit is going to be back to him in the morning to see what was going on. There were some spots where the voltage wasn't quite making sense and he's way better at this than I'll ever be so I'd rather not blow up the MS3 or my car!

Update: Brain fixed the issue on the megasquirt so I think that variable has been excluded.

It's still not working...

Here's what I know: the gauge unit itself will power up when connected to the battery. The display turns on, so that should be okay. Will an issue with the sensor cause the gauge to not display a reading?

This is what I tried today. I wired the wideband into the 12v source on the megasquirt. Nothing.
I then used an add-a-fuse circuit to add the wideband. Still nothing.
I switched the add-a-fuse to the radio to make sure it was working. The radio and gauges powered through the radio work, but the wideband display doesn't turn on.
On the first page, there was a brown wire that may have been a second ground. I spliced that to the main ground (black wire) for the gauge and used butt connectors to connect that to the ground off the megasquirt. Still nothing.

At most, the gauge blinks on for a split second sometimes but tit's legitimately for a split second.

I bought it used off a user here that said it was only run for an hour. I messaged him earlier to double check and see if he ever actually got it reading. I'm hoping it wasn't a bum unit.

At this point, I might just order another unit, which is going to friggin hurt... A friend is letting me borrow his wideband for the weekend and it is also an AEM unit, but one level down from the x-series. If the connectors are compatible, I'm going to try to swap head units to see if that's what's causing the issue, otherwise I might just order a new one on amazon or something so it's here early next week.

To add some icing to the cake, my battery finally died today after putting up with me for hours of this shenanigans. I tried jump starting the car to see if the wideband was giving a signal at all, and no dice.

Any advice would be appreciated. Even if it is to suck it up and dish out 175 bucks more after paying someone 150 for what may be a dud unit. I'm really hoping that's not the case but...

Update: Just heard back from the seller that it was working when he shipped it out and he sent video as well. So that's great, but now I'm even more confused haha.

And another update.

Just called aem and they walked me through a few things. Turns out the gauge is broken. I guess that explains why nothing made sense....

Seller's being a stand up gent and sent me his receipt. It was less than a year old and the unit is on its way back to AEM with an RMA. So my build is delayed yet again, but it seems like this will get fixed and only cost me the time and few dollars to ship it in.

sorry to dig up a dead thread but did you ever figure out whether that brown signal ground wire was necessary? I'm trying to get my car running on DIYPNP with the same AEM gauge/sensor kit and the gauge powers up /reads AFR fine it's just not sending to megasquirt/tunerstudio correctly. At first I had the white signal wire going into the harness at the stock location via the single wire connector cut off the stock O2 sensor. That only gave me a flat 19.1 AFR reading in my logs for when I tried to start the car so based on some recommendations here and elsewhere I sent that white wire directly to the DIYPNP O2 input via the DB15 connector and a jumper from O2 on the main board to the corresponding pin on the DB15 port. Tried to start again and now it shows AFR fluctuations in the logs but they're still obviously not correct. All I can think of at this point is that these newer UEGO units need the brown analog negative wire to be connected to signal ground on the DIYPNP but I'm not sure.