oh brother, for want of words to describe the problem.

EDIS and Megajolt installation related topics. Be sure to review the <a href="http://www.autosportlabs.net/MJLJ_V4_vehicle_installation_guide">Vehicle installation guide</a>

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alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

oh brother, for want of words to describe the problem.

Post by alexander »

hi all,
i am having problems with a fairly new installation.
installed a few weeks back. that worked straight off but for a phantom repetitive momentary ignition cutout. the map, tach and advance gauges all worked, save only for the apparently all too common issue with the serial/usb converter freezing the software. i dealt with that (eventually) buy buying a belkin brand converter, which seems to work without issue - so far.

viewed the pip and saw successfully with an analogue scope, but removed the mj for a few weeks while acquiring a digital pc based scope and new laptop battery so it could be run in the car while in motion. problem: that all done, now i have plugged the mj back in, there is no tach or advance reading, and the box is no longer controlling the advance.

*there is power to the mj, as confirmed with a multimeter, and the operating map gauge.
*the software will read the ignition map from the mj
*the pip appears not as a square wave, but as separate positive and negative spikes,
*........until i touch the case of mj with my hand, whereupon, the pip becomes a (slightly messy) square wave.

that is a far as i have gone at this point, so will have a more detailed look later after i have had a stress break.
i think there is something internally wrong with the mj - perhaps i have damaged it somehow?

thoughts, anyone?

alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

ok i will try to put in a couple of images from the scope...
first, the pip signal measured where just before the plug into the mj. the square wave is obviously not very square, and this is with my hand touching the case of the mj.
second, the same PIP signal, but without me touching the case.

there is no detectable SAW coming out.

what does it mean?
alexander.
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alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

ok i am going to answer my own question, for the benefit of anyone who might run into this sort of problem.
problem was the connecting plug. specifically, those pesky pins in the plug had pushed back too far into the plug, leaving the PIP signal pin out of reach of the corresponding pin in the mj unit.

i was measuring the the PIP signal before the connector, but had the scope earth wire on the mj body. somehow it was picking up a very weak signal getting into the mj (how??) via some path, a path which was significantly enhanced simply by me placing my hand on the case. not sure how, but there it is.

having detected that the PIP signal could not be seen on the mj side of the case mounted connector, i pushed the pins harder into the plug, and viola. we now have an operating device again with a SAW coming back out.

seems these connectors are a bit temperamental. naturally, a 14 pin molex jnr connector is that ONLY one i have been unable to locate in australia!

brent: if you notice this: i sent an enquiry to the sales email address of autosports.net asking if you can supply a couple of connectors, but did not get a reply. sorry if i am confused, but that is operated by you, is it not? anyhow, just wondering if i can buy a couple of the 14 pin connectors as i would like to remake my wiring loom, and start with a new connector and pins.

further general question: does anyone know if new EDIS connectors are available AND/OR how to remove / replace the pins in them? it would be a lot neater to solder straight to its pins, rather than splicing every wire onto the wire already there.

regards to all
alexander
sydney

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

Post by MartinM »

Glad you got it sorted :D ...and thanks for reporting it

I seem to remember seeing the specs for the Molex connectors in terms of rated insertions - it was something like 35, which is a suitably low number to make one remember that they might be a relatively weak link in the system (although I'm sure they're pretty damn reliable when connected properly)

More (?) importantly, what do you think of the DSO-2090 when used in anger? I've got a 2-ch 60Mhz analogue Tektronix and have been longingly looking at a 4-ch 60Mhz digital Tektronix for circa GBP1000, but maybe a DSO-2090-alike might be more realistic....

Dicky Blighter
Posts: 10
Joined: Fri Feb 22, 2008 9:58 am

Post by Dicky Blighter »

Not sure about new EDIS connectors but I do know you can't get the pins on their own.
However you can remove the pins. Using something like a jewellers flat blade screwdriver lift out the orange rubber seal around the wires, if you look into the connectoryou will see there is a plastic tag holding the pin in, gently push it away from the pin with screwdriver at the same time as pulling on the wire and the pin will come out. You can then snip off the crimped bit and there is a little well you can solder the new wire into. Sounds complicated but once you take the connector to bits it will make sense.

brentp
Site Admin
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Post by brentp »

Hi Alexander,

Glad you figured out your problem. I did send you a reply, but for some reason it didn't get through. Apologies for that, I will dig it up and resend.

The individual molex pins have barbs that catch the connector housing after they've been inserted from the rear. If these barbs do not engage the housing they will be pushed out backwards as you insert the plug. I'd recommend performing a tug on each wire to see if they will pull out; if they do, use a small screwdriver to re-form the barb and push it back into the plug housing.

What I suggested in my email was to try using a modified ATX power supply motherboard plug; apparently these have been known to work once you trim down the extra circuits. So have the reports indicated, at least.

In my experience the molex connector has proven to be been extremely reliable- at least 100 insertions on the race car and in the thousands on my test bench- it seems to be very under-rated. I have no doubt molex knows how to make a high quality connector! :)
Brent Picasso
CEO and Founder, Autosport Labs
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alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

martin: i must admit i am a complete newcomer to using an oscilloscope, so cant comment in any depth. i will say that, at AUD275 from ebay, the DSO is a very cost effective tool for this sort of thing. obvioulsy a 240v analogue scope isnt going to look good sitting on my girlfriends lap in the other seat of a lotus europa!! aside from that, the ability to take screen images, log data, and auto ranging make it very easy to use. on ebay oz at least, it was the only brand of pc plug in type DSO anyway (aside from a more expensive model). given the price you could buy two and use them as earrings.

dicky: thanks for the tip, i will give that a go.

brent: thanks for the info. i guess that means you cant supply the plugs individually, but that is totally fine, and was just asking. i will investigate the ATX plug idea as they are certainly readily available and only a hacksaw away from the right size. the problem in my case stems from the fact that i soldered the wires to the pins, lacking a proper crimp tool. i have subsequently acquired a better tool, but i found that putting solder on the pins negatively affected their final shape minutely ie i think they were a bit 'fat' where they should be crimped flat, and that has lead to them not seating properly in the plug. so there is another nuance of which to take note.

thanks to all and i will report back on all this later.

regards
alexander.

brentp
Site Admin
Posts: 6282
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Hi Alexander,

Please check your regular email regarding spare connectors. The ATX power supply connector trick was merely a suggestion for a potentially much faster and convenient solution for you! :)

david jenkins
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Contact:

Post by david jenkins »

One problem is when you insert the terminal into your crimping tool incorrectly. There are 3 tabs sticking out: 1 holds the sleeving, the second one holds the bare wire, and the 3rd guides the terminal in the casing. If you crimp all three then it won't stay in place - you have to leave the 3rd one uncrimped.

alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

david you are spot on about the crimping. my (limited) experience has been that, while properly crimped connections are the way to go, actually crimping them properly is not so easy. take, for example, your common and garden crimpable auto electrical connector - the type with red, blue or yellow hard plastic on the end. the crimping tools that are commonly sold for these are so useless as to make these connectors completely unreliable. i spent AUD60 on a decent tool, and it works a treat, but i had to go to an electronics hobby shop for it. auto parts shops (in oz) never have a useable tool. i noted with interest that this tool has about 20 different pairs of dies available separately, to suit all the different sorts of crimpable connectors.

moral of this: buy a quality crimper made to suit the type of connector/pin. not doing so only leads to bad connections, loose wires and a lot of grief.

adding a bit more here: i have been looking on-line for at crimpers and have not previously realised how many different types of crimpers there are! the molex brand crimper for the junior mini-fit pins is a mere USD400. for mortals, there is only one that that comes up for australia: AUD50. the same tool is USD14 from california, of course, but the postage to oz a cool USD80!

this is something to bear in mind for future construction.

i am going to post a new thread about this, lest it become lost in the not very specific topic i chose...

alexander.

nickj
Posts: 32
Joined: Sat Feb 17, 2007 7:52 pm
Location: Norway

Post by nickj »

I had a look on eBay for an appropriate crimping tool, without luck. There seems to be a wide array of possible ones! Could you possibly post a link to one of the right type?

Nick

alexander
Posts: 246
Joined: Sat Jan 19, 2008 4:33 am
Location: sydney, australia.

Post by alexander »

hi nick
this is where i bought some extra pins, and the crimping tool shown at the bottom (on its way in the post, so have not used it yet). of course, they are in australia, like me. they can post them, of course, so you might consider that a backup. i am sure there will be tools available closer, if only you can identify the right one!

i suggest looking for online electronics suppliers - i have seen a couple of UK sites, but cant recall their names - who sell the connectors and pins. they will likely have the crimping tools too.

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