I've just been running the tests again, everything connected as usual, when the engine stumbled for a brief second or two, then picked up again and the readings appeared on the laptop! Everything seems normal, RPM steady, advance dancing around 22-24 degrees.
After yesterday's testing when the laptop and MJLJ suddenly stopped communicating after 15 mins running, I decided to give the car a run for a couple of miles. All good so far, the car pulls strongly right up to 5500 ish RPM, no misfires, and certainly not the 'brick wall' effect at 3000 that I had previously.
Returning home I connected the laptop and everything is still reading correctly.
Following your advice I decided to resolder the connections to the RS232, oscilator and diodes, though none appeared faulty. With the RS232 I decided to take it completely out, clean everything, then re-fit.
All the soldering done, connected up the laptop and run the engine - everything still working fine.
Dry joints and/or poor connections on the RS232 could account for the intermittent link between the laptop and MJLJ, but would that have any bearing on the general operation of the unit (misfiring above 3000, failing to alter advance when engine speed increased?)
Is it possible that the 'electrical stress' you suggested the controller may have suffered could have been caused by poor/intermittent contact between the RS232 socket, PCB and link cable?
Although I don't drive the car with the laptop connected, I do have the link cable connected to the MJLJ. There is no weight hanging from the socket, in fact the cable is well supported below the MJLJ, it does however make me wonder.
It just stopped working!
Moderators: JeffC, rdoherty, stieg, brentp
Bob,
Good testing results, thanks for the update.
Regarding the theme of your question: The MJLJ processor has two major functions: 1- Control ignition advance with the EDIS module. 2- Communicate with a host system (PC w/config. software) to receive updated ignition maps, configuration data, etc. and to report runtime status.
These functions operate independently of each other, so it's conceivable that only one part of the system may be inoperable.
So the two basic ways to verify the unit is 'alive' is by evaluating the following:
1. Does it communicate with the software?
2. Is it controlling ignition advance (observing with timing light)?
With regard to your situation, it really seems that we fixed a problem around the two diodes in the power supply section, since there was a measurable difference after you did the repair.
It was good insurance to reflow the solder connections- in case you didn't, also reflow the joints on all of the 0.1uF capacitors. These are important for circuit stability.
Keep testing it and report back what you find- if you can, drive it for an extended period to see if you can catch it in a moment where you lose ignition advance control- something you'd be able to feel almost immediately.
Good testing results, thanks for the update.
Regarding the theme of your question: The MJLJ processor has two major functions: 1- Control ignition advance with the EDIS module. 2- Communicate with a host system (PC w/config. software) to receive updated ignition maps, configuration data, etc. and to report runtime status.
These functions operate independently of each other, so it's conceivable that only one part of the system may be inoperable.
So the two basic ways to verify the unit is 'alive' is by evaluating the following:
1. Does it communicate with the software?
2. Is it controlling ignition advance (observing with timing light)?
With regard to your situation, it really seems that we fixed a problem around the two diodes in the power supply section, since there was a measurable difference after you did the repair.
It was good insurance to reflow the solder connections- in case you didn't, also reflow the joints on all of the 0.1uF capacitors. These are important for circuit stability.
Keep testing it and report back what you find- if you can, drive it for an extended period to see if you can catch it in a moment where you lose ignition advance control- something you'd be able to feel almost immediately.
Hi Brent, Hopefully the problem is resolved, tests again today show that communication with the laptop is good and the controller is taking care of the advance correctly. I'll get a few miles in over the next week or so, and keep you informed of any developments - though I have a good feeling about it now.
Thank you, ever so much for all your help (and patience) I truly would have been lost without you.
On a different part of MJLJ, I have attached a picture of the bike carb set up on my Zetec engine. All the manifolds were home made, using bits from the scrap yard, and the intake balance plenum is just an old piece of exhause pipe that I welded ends on, then polished. The whole set up looks good and works well, which proves that you don't have to spend loads of money buying manifolds etc.
All the very best, Bob
Thank you, ever so much for all your help (and patience) I truly would have been lost without you.
On a different part of MJLJ, I have attached a picture of the bike carb set up on my Zetec engine. All the manifolds were home made, using bits from the scrap yard, and the intake balance plenum is just an old piece of exhause pipe that I welded ends on, then polished. The whole set up looks good and works well, which proves that you don't have to spend loads of money buying manifolds etc.
All the very best, Bob
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Hiperformance71
- Posts: 18
- Joined: Sat Jan 13, 2007 9:40 am
Hello to All!
Time ago, i have had a similar problem with one of my MJLJ installs, fixed advance (limp home mode of the EDIS) and no comunication with the Configurator sw, after some tests, checking soldering and others, i decided to pull out the processor from the PCB and insert it on another PCB of MJLJ (this working fine), after this PCB change, the new PCB don't communicate with the PC, after this i have plugged the "working" processor in the "faulty" PCB of MJLJ and it worked fine, at this point, i have realized, i have a bad processor or a erased firmware, i dont know, i have tried to update the firmware but no communication is possible, Fortunatelly, this is the only faulty MJLJ i have founded in a total of 7 MLJ i have installed (but 1 of this is out of service because this "problem"). The "faulty" MJLJ have worked fine for 2 weeks, Unfortunatelly, i dont have undestand why this is happened.
Brent, if do you want, i can send to you the "faulty" processor for analisis, if do you have a spare, can send it to me when i will made a new order of MJLJs V4?
Bests Regards to All,
HAPPY NEW YEAR!!!
Time ago, i have had a similar problem with one of my MJLJ installs, fixed advance (limp home mode of the EDIS) and no comunication with the Configurator sw, after some tests, checking soldering and others, i decided to pull out the processor from the PCB and insert it on another PCB of MJLJ (this working fine), after this PCB change, the new PCB don't communicate with the PC, after this i have plugged the "working" processor in the "faulty" PCB of MJLJ and it worked fine, at this point, i have realized, i have a bad processor or a erased firmware, i dont know, i have tried to update the firmware but no communication is possible, Fortunatelly, this is the only faulty MJLJ i have founded in a total of 7 MLJ i have installed (but 1 of this is out of service because this "problem"). The "faulty" MJLJ have worked fine for 2 weeks, Unfortunatelly, i dont have undestand why this is happened.
Brent, if do you want, i can send to you the "faulty" processor for analisis, if do you have a spare, can send it to me when i will made a new order of MJLJs V4?
Bests Regards to All,
HAPPY NEW YEAR!!!