No RPM with EDIS (coil disconnected)

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MadMax78
MegaSquirt Newbie
Posts: 27
Joined: Sat Jun 27, 2009 9:06 am

No RPM with EDIS (coil disconnected)

Post by MadMax78 »

Hi,

I just did a little test to make sure the RPM signal was working. My vehicle is running on it's original injection system (L-jetronic). The Megasquirt (MS II, board V3) is all wired up, except it is not connected to the IAT, CLT and injectors. I'm using Tunerstudio to monitor the sensors and everything is working, except for RPM. (RPM does work with stim) MS is connected to the EDIS module which is wired per this scheme:

Image

However, I have disconnected the edis coil, since I'm just testing and running the original dizzy and coil. The MS is jumpered like this:
V3.0 main board:

* DB37 pin #36 to the SAW pin (#3) on the ignition module
* DB37 pin #24 to the PIP pin (#1) on the ignition module
* On the V3.0 main board:
o use the 'Hall sensor circuit' (step #50.a in the assembly guide) - jumper D1 and D2,
o jumper OPTOIN to TACHSELECT on the bottom side of the PCB, near the DB37 connector, opposite the heat sink,
o jumper TSEL to OPTOUT on the bottom side of the PCB, near the center.
* jumper JS10 to IGN (this uses the processor port for the SAW signal directly),
* jumper XG1 to XG2 on the bottom side of the PCB, near the 40 pin socket,
and D2 is installed, but bridged.

Couple of questions:

- Does it matter that the EDIS coil is disconnected?
- Do I need to adjust the VR pots on the MS? Or aren't these used when using EDIS?
- If the wires on the VR sensor are the wrong way round, do I get 0 rpm, or something else? (I'm not 100% sure if they are on correctly)
MadMax78
MegaSquirt Newbie
Posts: 27
Joined: Sat Jun 27, 2009 9:06 am

Re: No RPM with EDIS (coil disconnected)

Post by MadMax78 »

Can't edit my post anymore... Just wanted to add that I used the following settings in TunerStudio:
Settings/MegaTune

In MegaTune, set:

* Trigger offset = 0° (this will vary slightly, depending on the wheel/pickup configuration),
* Ignition Input Capture to 'Rising Edge', ('Falling Edge' for MicroSquirt® only if using the VR input circuit - not recommended),
* Cranking Trigger to 'Calculated',
* Coil Charging Scheme to 'EDIS',
* Spark Output to 'Going High (Inverted)', ('Going High (Inverted)' for MicroSquirt).
* Trigger Wheel Teeth to '0' (zero)

Set the predictor algorithm option to 'last interval'.

DO NOT set the missing tooth settings to 36-1 - set the Trigger Wheel Teeth to zero - the EDIS module takes care of the 36-1 wheel - MegaSquirt-II sees it as a regular distributor.
Also just checked the wiring; wiring between MS and EDIS is ok, EDIS has 12v on pin 8, ground on pin 9. I guess it's starting to look like the VR sensor wires are swapped...
MadMax78
MegaSquirt Newbie
Posts: 27
Joined: Sat Jun 27, 2009 9:06 am

Re: No RPM with EDIS (coil disconnected)

Post by MadMax78 »

Swapped the wires and that fixed it... :mrgreen:

Now, need to make the sparkplug wires, do the initial setup and see if it'll run on MS 8)
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