Setting up ignition on megasquirt

So i'm in the process of trying to get the TB running, first time dealing with MS. I have all my sensors reading alright. Except for one the... Trigger. I'm running a dizzy with hall sensor, at first I had 12 v going to my hall and my board assembled for a 12v hall, with input to pin 24. I had a 5 v signal coming from the sensor on the return, whenever the window passed it ground it out so MS captures it on the falling edge ( after being inverted internally ). I had no signal in tuner studio not showing any rpm spikes or input at all.

I figured my Hall is actually a 5v so i did the board conversion to 5v, it now has a 5v ref+ and input to pin 24 also. Still no signal, actually worse off since the hall just read 4.5v at any time in rotation.

What am i doing wrong? Im running outta patience, need to be cruising out of the garage soon.

face_the_heat said:

Still no signal, actually worse off since the hall just read

Click to expand...

So when you rotate the distor by hand all you see is a constant 4.5v? If true sounds like an issue with the distro hall sensor not the MS unit.

need to know what bord you have v3.0? v3.57? and MS I? MS II?

A voltage of 4.5 should read just fine. I'm sending a voltage of 3.4v to my 5v capture on js10 and all is well.

Yeah that might help, sry wrote that in a different state. lol. Im running MS2 V3. And yes it just read 5 v on the output everywhere, vane or no vane. I tried to hook it up to 12 v and now it just reads on output 360* around. It seems like its grounding out all the time, faulty hall?

I also did the diode test checked the output. With my multimeter ground the black lead and checked for anything out of pin 2( output ) and it was reading 0v the entire way around.

hmm. Well I think your issue is with your distribuor, I cant help you there as Ive never ran a hall distro. I use the pickup on my bord (MS2 V3.57) so I can help you with issues on the MS not the Distributor.

I keep a VR sensor, and optical sensor that is known good on hand for testing my board input. Id start by plugin in a known good unit.

Soo. Got my new hall sensor installed but to no avail. WTF!? Wiring all checks out, but it still doesn't read above the voltage baseline of 1.8 Volts. What is going on? I have 11.xxxx volts at the positive, good ground, but signal voltage is too low. Hints?

Post the schematic of the input circuit you're trying to make. I suspect you're confused as to how a hall sensor works.

No, the schematic of the circuit you set up in the ecu. Or are you expecting the ecu to magically work without the proper input circuit?

The circuit used is for ms2 v3, hall sensor 12v, with ignition coil driver. But the MS was not hooked up for testing this morning. So its out of the equation right now

Unless you're supplying a 5v pull-up to the sensor output you won't be able to test the sensor.

Do you understand how a hall effect sensor works?

"In some cases, the Hall sensor doesn't produce a voltage signal, instead it pulls a voltage low. In these cases, you will need to attach a pull-up voltage and current limiting resistor to the signal line. You do this with a 5 or 12 Volt source (MegaSquirt will work with either voltage, check your sensor specs to see which it expects). " http://www.megamanual.com/ms2/pickups.htm

I'm a little confused too. I thought Face_the _heat had a distributor that had a 5v square wave hall sensor that did not pull to ground. There are 2 ways hall sensors work. 5v + sq out and pull to ground.

First type of hall sensor

SQUARE WAVE (+) going high
Normally if its a 5v sq wave it will have no volts (no signal to ground) then when the silicon flys by the magnate it makes a 5v sig.

SQUARE WAVE (-) going low
Odd version. you will have a 5v constant signal from the hall that goes to ground when the silicon flys by the magnate it makes a no reff sig.

Second type of hall sensor

5v going low
Normal type. 5v constant is sent to the hall sensor signal wire. When the silicon flys by the magnate the units pulls the 5v ref signal from the MS to ground.

5v going high. never seen it i don't know if it even exists.
Odd type. 5v constant is sent to the hall sensor signal wire BUT in this case the hall sensor is pulling it to ground so you will see 0v. When the silicon flys by the magnate the unit releases its hold(ground) and you get a quick blip of 5v.

Besides telling face_the_heat to get a known good unit for testing I should have made sure to ask him what type of hall sensor type Ive listed above he is working with.

Oh sometimes there 12V too. Just replace the above stuff with 12v if thats the case

LH distributors have a floating output and ground when triggered. They require a 5V pull-up to work properly.

It isn't very common in the automotive world to have a hall sensor that produce their own square wave. In fact, of all of the stuff I've MS'd the only application I've seen a sensor that produces its own square wave is the LSx cam and crank sensors and even those usually require pull-ups to function properly with MS.

LH distributors have a floating output and ground when triggered. They require a 5V pull-up to work properly.

It isn't very common in the automotive world to have a hall sensor that produce their own square wave. In fact, of all of the stuff I've MS'd the only application I've seen a sensor that produces its own square wave is the LSx cam and crank sensors and even those usually require pull-ups to function properly with MS.

I love learning new stuff! thanks gross polluter.

Ive always dealt with VR, OPTO, or points. never messed with a hall. I'm tempted to pull a unit at PNP this weekend when its 1/2 off day just to play around with it.

Also agree we need a nice picture of the current circuit on his MS board. A drawn diagram of what hes doing too.

OP please we want to help

Thanks a lot for your help so far fella's appreciate it, Ive been working nights so kinda lacking time to TB. Heres some photos of the board;
[/IMG]
[/IMG]
[/IMG]

The bosch impulse sender im using is this guy ( http://www.partsgeek.com/catalog/1987/volvo/245/engine_electrical/impulse_sender.html ) Im trying to find some specs if its a normally low or high, or a pull up any way I can test for this? Or a website that might have such facts?

,

I see:
R12 has 1000 ohms (OK)
R13 has 4.7k (OK)
C11 look installed (cant see value) (OK)

So every thing looks good until C30

Why are you jumping the top of C30 to S12C? You going ford EDIS???

Also top down photos next time Oh a pic of the back side of your board will help

This is an part of board asembly for hall sensors 12 volthttp://www.msextra.com/doc/ms2extra/build_manual.htm

Hall sensors Only (EDIS, VAST, luminition, etc):
a) Link OPTOOUT to TSEL
b) Solder a wire between TACHSELECT and XG1
c) For 5V inputs fit a 470R resistor into the position of R12
For 12V inputs fit a 1K resistor into the position of R12
d) For 5V inputs solder a wire between the top hole of C30 and 5V on the proto area.
For 12V inputs, solder a wire between the top hole of C30 and s12c pad on the main board.

Is that alright? also im using the "trigger return" for setup on tuner studio