MSefi.com read only forum (Jan.15,2018)

Hi guys,
Could some one please help me if I am missing something ? The car starts but rough meanwhile when I make the jumps xg1-xg2 and tach to optin it doesn't start at all , help please

Thanks in advance

FWIW...... I am not sure I like those coiled up wires. Coiling wire certainly makes a nifty inductor , but it's something that might also cause issues somewhere down the road.........

Not a huge deal, but worth mentioning I think..............

Ken

Point taken but Is it important to assemble all the resistors or it's okay ?

Thanks

Which hall effect sensor are you using? Some need a pull up resistor added.

Here it is !

Not much help here, I'm afraid. If it's a stock dizzy, have you looked on the MS site for connection diagrams for that exact one?

The car was okay for a long time but suddenly the ignition driver IC was burned and after I changed it , this issue came anyhow I will try to google today , thanks anyhow !

The hall sensor supply voltage is 12V and the output is the same as well, when it's on the metal side it shows 12v and when the open area arrives it's almost 0V , is it correct ? Meanwhile is it rising edge or falling edge ? One more thing , I didn't connect any resister I guess I have to as the manual , I am I correct ? Please help

You need to find the appropriate diagram and mods to MS for using 12v from a hall sensor into the opto input.

Are you running B&G or Extra code? They have different ways of configuring the hardware. So refer to the manual appropriate to the code, and only that one.

The ignition is really in two bits as far as this is concerned.

The input section that reads the tach signal needed by MS for everything.

The output stage(s) to drive the coil(s)

Either could have a fault - but a fault on the output stage shouldn't stop the tach signal working.

The current output driver is a BIP373 - these are usually pretty bomb proof.

I got the fault but one thing I want to know is the normal Hall effect jumper settings with xg1-xg2 doesn't work on my device why is that ?

Thanks

Is XG1 connected to something else? When linked they provide a ground from MS ground for the LED in the optocoupler. The link is to allow a different way of grounding the LED.

Yes XG1- Tachselect
Tsel-optout
It's working like this but if I make Tachselect -option and xg1-xg2 it doesn't work in the stim and car. Do I have to correct something or its good to go ?

Thanks

As I said, there are options on how things are connected according the type of sensor and so on. Stick to the diagram for yours.

If your Hall sensor is giving you a 0 or 12 v output when the sensor output pin is not connected to anything, then it has an internal pull-up arrangement. There is no general statement about 'correct' as to whether the voltage is high or low when the metal or window is present next to the sensor as its an active sensor and can have an inverted output. The more common arrangement would be that the sensor output goes to the ground state when the metal is next to the sensor element and then floats or goes high (with internal pull up) when the window is next to the sensor element; but, that does not have to be the only arrangement.

If you have Xg1 connected to Tsel you are likely operating the sensor in the ground switch mode. When the sensor output goes to 0 volts it is applying a ground to Xg1. This switches the 4n25 opto isolator on. When the sensor Hall sensor output goes to 12 v it switches the opto isolator off. Off course, for this to work in this mode you must apply Vcc to the input of the circuit on Opto in. I see that D1 and D2 are jumpered which is correct for a Hall / Optical sensor. However, I don't see anything connected to the Opto in jumper point. Are you getting Vcc some place else?

You said the ignition driver IC was burned. Do you mean the 4n25 opto isolator (U3) or the BIP 373?

I gather you are doing single coil spark control with the MS? From an electronics perspective, you can trigger on the rising edge or the falling edge of the sensor output, it will just alter the positioning of the distributor. It is possible that selecting rising or falling may make the phasing of the distributor rotor a problem and prevent the engine from operating. If you switched from ground switching the opto isolator to applying the input on opto in, you end up inverting the tach signal through the opto isolator circuit, which will severely screw up your ignition timing.

Ground switching is a good arrangement; but, would not be my preferred arrangement with a sensor with internal pull-up.