RPM signal

[ellis9436]

Hi guys.

After a while of not being able to get the megajolt to work properly, it now is apart from, there doesn't seem to be any RPM signal being displayed on my laptop.

The Load display is working nicely and i assume as it should. My Tacho on the dash shows a reading, although thats running off the missing pin on the Edis connection.

Is it important to be able to see the RPM on the laptop for tunning issues? If so, has anyone got anyideas as to why its not working?

[MartinM]

To keep it's displays up to date, the Configurator periodically (and quite often!) asks the MJLJ to report back what it is is measuring, does some calculations and then displays the results on the PC

The MJLJ reports back the current map cell, the load (TPS or MAP), the programmable output statuses and the RPM.

So you're saying you see all of them on the PC display, but the RPM is stuck at zero when the engine is running?

[brentp]

So it appears from your description you do not see the RPM activity on the screen but otherwise can communicate with the controller?

The MJLJ calculates the RPM from the PIP signal, and also uses it to send the 'SAW' word back to the MJLJ, in order to signal the desired ignition advance.

It seems in your case the MJLJ cannot read the PIP signal. Double check the wiring for the unit- make sure the PIP line on the EDIS module is feeding into the correct line on the MJLJ.

We also have this covered in the troubleshooting guide. http://www.autosportlabs.net/Troublesho ... lt_Lite_Jr.

Without an RPM reading you should also *not* see the ignition advance change when using a timing light- the EDIS module will be in it's 'limp home' mode, fixed at 10 degrees BTDC.


Let us know what you find,

[ellis9436]

Completely uterly my fault!

Double checked the wires, and had plugged the PIP wire into the wrong connector
It was plugged into the userout 1 plug, would that have caused any damage to the megajolt unit? seems to be all ok

[brentp]

*probably* not. If you are now getting an RPM indicator you likely didn't damage the Edis module. Likewise, in the future if you use user output 1 you'll be able to tell if it was damaged.

If the pip output is current limited in the edis module everything should be ok.

go enjoy your new engine!

[MartinM]

Hi guys.
After a while of not being able to get the megajolt to work properly, it now is apart from, there doesn't seem to be any RPM signal being displayed on my laptop.
....

So I guess it's working substantially better now

Have you checked with a timing light that the timing is now actually changing?

It's not a great idea to plug the PIP from EDIS into a programmable output, but if it all seems to work OK, then you've probably got away with it. Are you using the programmable outputs for anything?

[ellis9436]

I have no plans at the moment for using the programable outputs.

Lets hope i do get away with it!