cowlover556

iTrader: (1)

Hello,

Finally started doing turbo stuff and wanted to start with wiring the ECU so I can troubleshoot everything before swapping the spoolysnail on. I have a MS3Pro PNP and 3 gauges that I want install. Car is a NB2

The first is an AEM X-Series UEGO. Based on the documentation for both the gauge and the ECU (diagrams below) I have wired the white wire (analog output) to pin C (analog input) of the MS3 option connector. I've searched on this forum where people are getting power for the gauge and it seems that the window switch is fine according to some people, and not fine according to others... I've also read that grounding gauges to the ECU ground (pin A on the option connector) is a no-no.

The second is an AEM oil pressure gauge. This one does not need to be wired into the ecu but it can be done for datalogging purposes. I dont think I will it to the ecu but I still need to supply power and ground.

The last is a boost gauge from FM. The power and ground will be wired to the interior light dimmer switch.

So my questions are:

​​​​​​1. Should I pull 12v switched from the power windows, ignition or some other secret spot?
2. How many gauges can I wire into the same power/ground?
3. The analog output has a ground (brown wire). Since MS does not use differential analog input, can the brown wire be grounded to the same spot as the power ground? Or does this one have to go to pin A?

Thanks in advanced, sorry for the nooby question!


MS3 Pro PNP Options connector

X-Series Connector A pinout

newold_m

iTrader: (2)

Watching with interest as I have an X series on the way and will be getting a MS soon as well.

Graxis

I'm using the AEM X-Series. I used a fuse tap from an "always on" circuit (can't remember which circuit at the moment; chassis is 96 NA8) to prevent cycling the sensor warm-up twice: once when turning the key on and again after cranking.

I used the CAN output and highly recommend doing the same if possible with your setup. No worrying about grounding issues or calibrating for differences between the gauge and MS.

cowlover556

iTrader: (1)

I was under the impression that the CAN output was only for AEM ECUs. What are the differences/advantages of the CAN output instead of analog

Graxis

Advantage: MS receives exactly what your gauge displays. When I first installed my X-Series, I tried several different grounding schemes and always had to adjust the sensor calibration in TS to get it to read the same as the gauge. Check the MSExtra manual for the current CAN capabilities; ie, AEM CAN devices don't allow you to use non-AEM or the MS-specific CAN protocol, at least when I set mine up. Not a problem for me at the moment because the wideband is my only CAN device.

Here's a screenshot of my CAN settings in TS.

cowlover556

iTrader: (1)

Did you have to wire both the high and low line for CAN? Im sending the car to a tuner in SoCal so I wont have to deal with the gauge and ms not showing the same value in tuning, but i suppose it would be advantageous to see what the actual AFRs for peace of mind

cowlover556

iTrader: (1)

​​​​​​​After bugging people on the MT.net FB group I've decided to go with a distribution block powered directly by the battery with a relay wired into the cars ignition. Might be overkill but itll give me a ton of peace of mind when/if I decide to add more digital gauges (oil temp, air temp, digital boost gauge ect)

Graxis

I wired both high and low.