Installation issues?

General Topics for configuring, operating and tuning the Megajolt. Also see the <a href="http://www.autosportlabs.net/MJLJ_V4_Operation_Guide">Operation Guide</a>

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rogerrally
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Joined: Fri May 05, 2006 9:55 am

Installation issues?

Post by rogerrally »

Hi

I have a version two megajolt that i have had kicking around for over a year, waiting to be installed.

I have over the christmas hols found time to lash in the Ford EDIS and the megajolt, its not very elegant but it is only temp to prove that it works before installing it neat and tidy.

I have updated the firmware to the latest (2.5.0) and i have used configurator v3.0 beta 3 and beta 4.

The problem that i am getting is that the rpm is displaying 457 rpm without the engine running, and when i rev the engine up the rpm reading starts flicking all over the place.

It is currently running in 2D mode, on a Vauxhall 1400cc 8V rally engine with cam and twin 40s.

Can any one advise?

Cheers
Roger

brentp
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Robert,

Post by brentp »

Robert,

Can we safely assume your engine is running fine at 10* BTDC with the MJLJ disconnected?

Can you verify you connected the PIP and SAW according to <a href="/mjlj/?q=node/14">this pinout</a> on your V2 controller?

Could you point us to the firmware file you used to update your controller? We need to make sure you used the correct one for your unit.

Brent Picasso
CEO and Founder, Autosport Labs
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robert verhey
Posts: 5
Joined: Wed Oct 18, 2006 7:42 pm

Wiring schematic for Megajolt 3.0

Post by robert verhey »

Brent,

I haven't come so far yet. But your link "this pinout" gave me the information I was after.

Thanks,

robert verhey
Finspång, sweden
robert verhey
Finspång, sweden

brentp
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Robert, if you have a V3

Post by brentp »

Robert, if you have a V3 controller, you should reference the V3 documentation: <a href="/mjlj/?q=node/606">here</a>

You can access the root of the documentation from the "Documentation / Information Library" link above.

Brent Picasso
CEO and Founder, Autosport Labs
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rogerrally
Posts: 0
Joined: Fri May 05, 2006 9:55 am

Hi It seems that this thread

Post by rogerrally »

Hi

It seems that this thread has been hi jacked?

I am running a V2 megajolt, that i have updated to v2.5.0 firmware (downloaded from this site) and using configurator 3.0 beta (tried 3 and 4).

My car runs fine on EDIS only, with the Megajolt removed (except at 30 degrees instead of 10, but i think thats down to my trigger wheel /sensor mounting).

I have wired my pinouts as per the link. I only have 12v GND and PIP and SAW connected to Megajolt.

Cheers
Roger

robocog
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Joined: Wed Jun 07, 2006 11:57 pm
Location: Gosport Hants
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I'm not an expert

Post by robocog »

I'm not an expert but...

Could be HT noise causing the rpm to be all over the place I suppose?
Noise spikes caused me lots of niggling intermittent problems at first
Changing plugs and leads for decent suppressed resitor type ones , checking that all connections and earths were clean and good seemed to cure it
I grounded the coilpack and the MJ unit case as well for good measure and the only time I have seen the shift lights flicker unduly since (they are brilliant for diagnosis!) was when I used a Gunson colourtune to set the fuel mixtures
(it uses a non supressed glass faced spark plug and solid core HT lead so unsurprising really)

Is the MJ unit and cabling sited well away from all noise sources as far as is practical?
Also may be worth checking that the VR sensor is wired the right way round? not sure if this would do similar tricks if reversed?
Also does the VR sensor cable have the outerbraid ground? is this connected to earth?

Not sure if you have an osciloscope to see if you can see the noise, if thats what is causing it?
It may help to chase it to a single HT component rather than having to replace plugs, leads, coilpacks etc blindly

Good luck chasing the problem
Its really worth the effort once up and running :-)


________
vaporizer shop
Last edited by robocog on Tue Feb 01, 2011 8:39 am, edited 1 time in total.

MartinM
Posts: 433
Joined: Sat Aug 27, 2005 12:08 pm

I thought the 457rpm

Post by MartinM »

I thought the 457rpm observation was a firmware problem that had been fixed?

brentp
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Joined: Wed Jan 24, 2007 6:36 am

It's not a firmware problem

Post by brentp »

It's not a firmware problem per se- it's the lowest measurable RPM based on the internal timer overflowing in the processor.

It's really the configurator / tuner's interpretation of the raw RPM value. For purposes of setting ignition advance, the controller interprets it correctly.

So if it's 'fixed' anywhere it would be how it's displayed in the tuner software.

Brent Picasso
CEO and Founder, Autosport Labs
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brentp
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If the RPM is jumping around

Post by brentp »

If the RPM is jumping around then the MJLJ may be seeing spurious signals on the PIP line.

Another source of problems might be if you're accidentally running 3.x firmware on your 2.x controller. If you're absolutely sure you're running 2.x firmware then then you can look into how clean the PIP signal is, using an oscilloscope. Related to this, you should also ensure the EDIS and MJLJ are grounded at the same location.

The reason why I emphasize the firmware is that it's unfortunate you flashed a new firmware version before testing your engine with what it already had installed: multiple variables have now been introduced, and we need to work a bit more to get back to a baseline.

Brent Picasso
CEO and Founder, Autosport Labs
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