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-   -   MS1 Brainsquirt No Spark No Injectors No Comms with Laptop (https://www.miataturbo.net/megasquirt-18/ms1-brainsquirt-no-spark-no-injectors-no-comms-laptop-76658/)

vitamin j 12-21-2013 08:12 PM

MS1 Brainsquirt No Spark No Injectors No Comms with Laptop
 
Been trying to diagnose a recent non-start on my Miata. Car is a '96 with a MS1 Brainsquirt.

About 3 weeks ago after installing my new injectors and turning up the boost I was driving and after a fast pull I coasted and the motor died, would not restart. I coasted into a gas station thinking I just blew my motor but after inspecting it everything looked fine. About 5 mins later I tried restarting and it started right up and ran fine.

It ran absolutely great for the past 3 weeks until Thursday when it died on my way to work. Wouldn't restart right away but then started up again just fine a few minutes later. Then during the same journey it died again and would not restart, had to tow it home.

At first I thought it was the fuel pump because I couldn't smell any gas and the pump is original with 190k. Pump is fine though.

Injectors won't pulse and on top of that I'm getting no spark.

I initially diagnosed it to a bad CAS, but after searching around I thought to bring my laptop out and the MS1 will not communicate with the laptop. I was just tuning with it the other day so it's gotta be related.

I'm done working for tonight but am hoping to get a few ideas of things to check tomorrow so I can drive in to work on Monday. I am going to start by hooking up the stock ECU again and seeing what happens.

So I have 3 big issues, no injector pulses, no spark, and no communication between the laptop and MS1, any ideas?

vitamin j 12-21-2013 08:36 PM

Just checked and the MS1 board and all components look fine.

vitamin j 12-22-2013 01:04 PM

Usually I get the 2 outside lights on the MS1 illuminated, but now only one is illuminated. What's that mean?

e: D14 is illuminated, D16 is not.

vitamin j 12-22-2013 01:47 PM

Ok I dunno what I changed between that last post and now but now only D16 lights up and D14 doesn't. Could this be a back coilpack or should I look into wiring?

I disconnected the coilpack and none of the LEDs illuminate.

vitamin j 12-22-2013 01:59 PM

My coilpack has a little protrusion pretty much exactly like this one:
https://www.miataturbo.net/megasquir...67/#post189840

Could it be that simple? Could a failing coilpack produce the intermittent failures like I had earlier? I was under the impression they either work or they don't.

hector 12-22-2013 04:55 PM

I would look at the power supply to things like the coils, injectors, and ecu. If its a relay and under the hood it may be getting too hot and going "open". A bad coilpack wont affect fuel pulse or ecu operation.

Braineack 12-23-2013 08:46 AM

The lights on the MS have nothing to do with the coilpack and everything to do with the tune/state of the MS itself.

it sounds like the tune on the MS itself could have been compromised; you tend to only see D14 only lit up when there's no tune present on a freshly loaded firmware before any map is loaded. D14 & D16 light up because of the settings with the specific msq tune...

and especially coupled with the fact you're having difficulty connecting to it with a laptop. My guess is is that the firmware had been corrupted and you need to reflash it using a boot jumper and reload the tune.



THAT or the harness is wired for a vTPS and you still have the stock one present and you plugged the stock TPS back in randomly one day without thinking and now you have a ground fault locking the unit up...

vitamin j 12-23-2013 09:37 AM

Haven't changed anything on the MS except the tune for the past 6 years.

While looking at my coilpack I noticed two of the wires on one of the connectors were damaged and there might have been a possible short. That would make sense for the intermittent stalls. Now I'm worried that when those wires shorted the last time they may have taken out a circuit in the MS.

After searching around I thought everything I read said that those LEDs had to do with the ignition circuit, but maybe I was reading the wrong application.

Braineack 12-23-2013 09:53 AM

they do, but the MS CPU controls the lights on the MS, the coilpack has no bearing...

vitamin j 12-23-2013 12:35 PM

Ok, do you think I could have damaged the MS when the coil shorted or should I try re-flashing it?

Dunning Kruger Affect 12-23-2013 12:47 PM

Reflash it.

Dunning Kruger Affect 12-23-2013 12:48 PM

As in reflash the coilpack.

vitamin j 12-24-2013 01:05 PM

Yeah well that's what I'm hoping to avoid lol.

vitamin j 12-31-2013 03:22 PM

Still not able to connect with the MS. I've tried to reflash the firmware a bunch of times but HyperTerminal isn't able to connect with the MS either.

Are there any known issues with HyperTerminal and Windows 8? Lots has changed since 2005 so I'm wondering if maybe there's a problem on the computer end.

Does anyone have an idea of what might have been damaged on the MS? Would it be easier to fix this MS or buy another?

Fireindc 12-31-2013 05:26 PM

I'd take the chance to upgrade to ms2 or better, good luck though Jimmy.

vitamin j 01-01-2014 02:36 AM

Yeah I have thought about that. I just want to get it back on the road fast and for the lowest cost. Been driving my gf's beater 95 Celica and it sucks. An upgrade would be nice but I'd be perfectly happy with soldering on a new part if I just knew what got fried when the coilpack shorted.

vitamin j 01-03-2014 01:11 PM

3 Attachment(s)
Here's a picture of the damaged wires, it's hard to see but both the black and blue wires have damage exposing them. I haven't been able to figure out where these wires end up in the MS but I'm going to spend more time tonight.

Dunning Kruger Affect 01-03-2014 01:23 PM

That's the power and ground to the coilpack.

vitamin j 01-09-2014 01:08 PM

2 Attachment(s)
Does this mean my MS is fucked?

vitamin j 01-18-2014 10:55 PM

The wire damage I posted earlier was not the cause, but thankfully led me to the cause of my problems. I still had a short between the coilpack 12v and ground. I traced it back to the Meter fuse which then led to a black/yellow wire which carries 12v all over. I traced that to the harness that goes between the driver's side kick panel back under the door, behind the fuel tank, and narrowed down the short to the power antenna harness. Wtf. That harness behind the fuel tank is totally inaccessible so tomorrow I will just pull the pins for that wire out of the connector to bypass that whole harness. Must have been snow melt leaking down on to that harness or something.

Oh ya and I have an MS3X now.


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