Hi, i've just received my new built MJLJ(thanks Brent) and was wondering what do i do now?
I understand electronics etc but i'm unable to find a 'how to' guide for this setup
what i need to know is;
do i need to upload anything to the mjlj? other than maps etc
what is bootloader and firmware?
what is the difference between high and low outputs on the v3 board in the user config outputs?
is there a 'how to' guide for dummies or an instruction manual for the mjlj?
thanks in advance
Tom
What do i do now?
Moderators: JeffC, rdoherty, stieg, brentp
Hi Tom, The starting point
Hi Tom,
The starting point for the documentation can be accessed via the link at the top. See the MJLJ V3 section. As you will see, much of the information covers the construction of an actual MJLJ unit. You will need to review the last step, covering vehicle installation.
This is where the instructions end, and as you and at least one other person pointed out, the rest may be non-obvious. So we certainly need a few more sections to get you to a working installation.
These are the basic steps required to get your MJLJ running:
1. Install the Ford EDIS system and verify it is working on your engine. see the information library and the other technical info, links above. This involves installing an appropriate crank trigger wheel, crank sensor, coil packs and the EDIS module matching your engine configuration (4,6, or 8 cyl.)
2. Once you have verified the EDIS module is controlling your ignition, you can wire in the MJLJ. See the <a href="/mjlj/?q=node/606">vehicle installation</a> section.
3. install the configuration software, connect your PC to the MJLJ using a serial cable, and start tuning your engine.
Here are the answers to your specific questions, and a bit more to get you started:
The completed unit you received already has the firmware installed- no need to worry about installing bootloader/firmware. On the included firmware is a 'safe' ignition curve that should work fairly well for most engines.
Download the configuration software (See 'software' link at the top). There is a quick readme included with this to get you started. Note the default firmware is configured for a 4 cylinder engine. If this is not what you have, you can use the software to change it.
The 'high' vs. 'low' on the outputs refer to the behaviour of the output when the configured threshold is crossed. If it is configured as 'high' the controlled device will be enabled once the configured value is reached. If 'Low' is selected, the controlled device will instead be turned 'off' when the threshold is crossed.
'high' and 'low' is a bit of a misnomer, it really means 'normal' and 'invert'. Here's a concrete example:
You have a LED lamp controlled by user output 1, and You want the LED to turn on at 4000 RPM. You would configure the output as type 'RPM', value '4000', and mode 'High'.
If you changed the mode to 'Low', the LED would be on below 4000 RPM and would turn off at 4000 RPM and above.
I hope this helps for now, I think your question has prompted me to do a round of documentation enhancement!
Regards,
The starting point for the documentation can be accessed via the link at the top. See the MJLJ V3 section. As you will see, much of the information covers the construction of an actual MJLJ unit. You will need to review the last step, covering vehicle installation.
This is where the instructions end, and as you and at least one other person pointed out, the rest may be non-obvious. So we certainly need a few more sections to get you to a working installation.
These are the basic steps required to get your MJLJ running:
1. Install the Ford EDIS system and verify it is working on your engine. see the information library and the other technical info, links above. This involves installing an appropriate crank trigger wheel, crank sensor, coil packs and the EDIS module matching your engine configuration (4,6, or 8 cyl.)
2. Once you have verified the EDIS module is controlling your ignition, you can wire in the MJLJ. See the <a href="/mjlj/?q=node/606">vehicle installation</a> section.
3. install the configuration software, connect your PC to the MJLJ using a serial cable, and start tuning your engine.
Here are the answers to your specific questions, and a bit more to get you started:
The completed unit you received already has the firmware installed- no need to worry about installing bootloader/firmware. On the included firmware is a 'safe' ignition curve that should work fairly well for most engines.
Download the configuration software (See 'software' link at the top). There is a quick readme included with this to get you started. Note the default firmware is configured for a 4 cylinder engine. If this is not what you have, you can use the software to change it.
The 'high' vs. 'low' on the outputs refer to the behaviour of the output when the configured threshold is crossed. If it is configured as 'high' the controlled device will be enabled once the configured value is reached. If 'Low' is selected, the controlled device will instead be turned 'off' when the threshold is crossed.
'high' and 'low' is a bit of a misnomer, it really means 'normal' and 'invert'. Here's a concrete example:
You have a LED lamp controlled by user output 1, and You want the LED to turn on at 4000 RPM. You would configure the output as type 'RPM', value '4000', and mode 'High'.
If you changed the mode to 'Low', the LED would be on below 4000 RPM and would turn off at 4000 RPM and above.
I hope this helps for now, I think your question has prompted me to do a round of documentation enhancement!

Regards,
Thanks brent that
Thanks brent that helps.
just to confirm. High = open circuit until 4000 rpm is reached then its grounded
Low = grounded changing to open circuit when 4k is reached
i dont really understand the load and rpm bins bit on the configurator but i haven't even fitted the engine yet so will pick your brains on that nearer the time.
thanks again
Tom
just to confirm. High = open circuit until 4000 rpm is reached then its grounded
Low = grounded changing to open circuit when 4k is reached
i dont really understand the load and rpm bins bit on the configurator but i haven't even fitted the engine yet so will pick your brains on that nearer the time.
thanks again
Tom
martin i think you just
martin i think you just contadicted brent with the high/low outputs?
I'm glad that helped- and
I'm glad that helped- and yes, you're correct on your assumption of the outputs.
** Martin, I believe you have the high / low behaviour backwards..
** Martin, I believe you have the high / low behaviour backwards..

...do i need to upload
<b>EDIT:</b>high/low interpretation corrected!
...do i need to upload anything to the mjlj? other than maps etc..
No, just configure the map using the configurator
...what is bootloader and firmware?...
http://en.wikipedia.org/wiki/bootloader
http://en.wikipedia.org/wiki/Firmware
Suffice to say here that they are both inside the processor inside the unit, so you don't need to worry about them
...what is the difference between high and low outputs on the v3 board in the user config outputs?...
If set to high, then the transistors inside the ULN2003 are switched on when the triggering condition is true (e.g. a LED and resistor wired between +12v and programmable output will light at the triggering condition). If set to low, the transistors are switched off at the triggering condition (e.g. a LED and resistor wired between +12v and programmable output will go out at the triggering condition)
...is there a 'how to' guide for dummies or an instruction manual for the mjlj?...
It's worth looking at http://www.cate1.co.uk/megajolt, especially
http://www.cate1.co.uk/megajolt/loom.php
http://www.cate1.co.uk/megajolt/installation.php and
http://www.cate1.co.uk/megajolt/mapping.php
Anything else, just ask here!
...do i need to upload anything to the mjlj? other than maps etc..
No, just configure the map using the configurator
...what is bootloader and firmware?...
http://en.wikipedia.org/wiki/bootloader
http://en.wikipedia.org/wiki/Firmware
Suffice to say here that they are both inside the processor inside the unit, so you don't need to worry about them
...what is the difference between high and low outputs on the v3 board in the user config outputs?...
If set to high, then the transistors inside the ULN2003 are switched on when the triggering condition is true (e.g. a LED and resistor wired between +12v and programmable output will light at the triggering condition). If set to low, the transistors are switched off at the triggering condition (e.g. a LED and resistor wired between +12v and programmable output will go out at the triggering condition)
...is there a 'how to' guide for dummies or an instruction manual for the mjlj?...
It's worth looking at http://www.cate1.co.uk/megajolt, especially
http://www.cate1.co.uk/megajolt/loom.php
http://www.cate1.co.uk/megajolt/installation.php and
http://www.cate1.co.uk/megajolt/mapping.php
Anything else, just ask here!
Not for the first time....!
Not for the first time....! (not helped by Configurator V3.0.0 beta 2 getting them the wrong way round as well!)
I've corrected my post
I still can't think of the best term for them as I don't find High and Low very intuitive - I think On and Off aren't too bad?
On - a device between +12v and the output pin will be turned on at the trigger point
Off - a device between +12v and the output pin will be turned off at the trigger point
I've corrected my post
I still can't think of the best term for them as I don't find High and Low very intuitive - I think On and Off aren't too bad?
On - a device between +12v and the output pin will be turned on at the trigger point
Off - a device between +12v and the output pin will be turned off at the trigger point
Normal / Invert
LOL
I'm still trying to wrap my head around it. The high/low concept came from the output on the processor, which feeds into the base of the switching transistor. But of course, someone using or configuring the output won't care about those details.
I'm settling on "Normal" and "Invert"- I think that's the most accurate description of the behaviour. Describe the "normal" behavior, and "invert" relative.

I'm still trying to wrap my head around it. The high/low concept came from the output on the processor, which feeds into the base of the switching transistor. But of course, someone using or configuring the output won't care about those details.
I'm settling on "Normal" and "Invert"- I think that's the most accurate description of the behaviour. Describe the "normal" behavior, and "invert" relative.
How about Greater than
How about
Greater than and
Les than
Conrad
Greater than and
Les than
Conrad