LS1 5.7 Cam and Crank sensor not reading

[kappa]

Hey guys! so i am just about finished my LS1 FD and im at the point of starting the motor. right now i can not get the cam or crank sensor to give me any readings. im using MS1 with MS3 daughter board and chip plus im using the relay board from ms1 to make things easier to connect.

anyway i have tried to wire these two sensors all different ways but it should be easy.

1 goes to 12 V then i have my shielded wire that goes to ground and one to signal... okay great so why cant i get anything to show? i went and bought a new part for the board because on diyautotuners it says it wont work with the ls1 and i turned my resistors all the way counter clockwise and nothing... as im sure you guys can tell im new to MS but have a friend whos been helping me get this far. anyone have anyway to trouble shoot what im doing wrong? any help would be awesome

[Matt Cramer]

First:

1. Is this a V3.0 or V3.57 board?
2. How are the ignition input jumpers set up?
3. Does it get a good signal on a Stim?

[kappa]

First:

1. Is this a V3.0 or V3.57 board?
2. How are the ignition input jumpers set up?
3. Does it get a good signal on a Stim?

Hey Matt thanks for the response

1. V3
2. Setup as per DIYAutoTune specs state for the ls1
3. not 100% sure if i got this right by the term stim but i did do a test with the laptop and i see to be getting some electric pulse like its counting teeth but no real readings

[Matt Cramer]

Stim - the Stimulator board. There currently isn't one that puts out an exact duplicate of the LS1 crank sensor pattern, but you could at least test it to be sure the circuit's working.

[volospian]

I had all sorts of issues getting mine to work, but mine was ms3/ms3x so it may be different.

First, check this link: http://www.msextra.com/doc/ms3/ls1.html as it has the correct wiring for the ls1 sensors

If you think it's wired correctly, before opening the ms check what I didn't.... get a multimeter and measure the voltage from the engine block back to the battery -ve. There should be something like less than 0.5v or so during cranking. My earth was a bit duff and i was getting ~1.5v due to the resistance. This was causing the cam signal to go wild.

Then, check the vr pots are set correct for ls1. Not sure what difference it makes on yours, but on the ms3 the ls1 crank settings need to be fully ccw, then r56 is wound 6 turns cw, iirc. It could be worth looking at the ms3 settings here: http://www.msextra.com/doc/ms3/ignition.html#tachint

good luck,
Rich.

[kappa]

Thanks guys excited to try that tonight. I am using the new shielded wiring from diysautotuners and I am using the centre wire as well as what looks like the second wire all in one. Could this be causing me issues?

[kappa]

To make sure I am clear I got the single shielded wire and I'm using I guess the centre wire and the shield part for my sensor. This has got to be my issue thinking about it now it made sense to do it that way at the time but that's gotta cause major issues would it not?

[BigLou240sx]

To make sure I am clear I got the single shielded wire and I'm using I guess the centre wire and the shield part for my sensor. This has got to be my issue thinking about it now it made sense to do it that way at the time but that's gotta cause major issues would it not?

That does seem to be an issue - my understanding is that the shield should not be used to carry ground, it should only be connected to ground at one end to shield the inner wire. Sounds like you need to run a dedicated ground wire out to your sensor

[volospian]

Don't use the shielding as an earth, as BigLou says. My kit had two wires inside the crank cable, one for earth and one for signal. If yours only has one wire inside you need to use that for the signal and run a seperate ground to the sensor. I'm not sure it makes much difference which earth wire you use as long as it's directly back to the ms (I.e. don't earth to the block), but I was told to use the main sensor earth for my cam connection.

Rich.

[kappa]

What do you guys mean by earth ground. meaning the ground on the MS3 wire harness that goes back to the ecu?

[Ollie8974]

No the ones that go to Good Engine Ground.
This link.
http://www.msextra.com/doc/ms3/ls1.html
The grounds that go back to the ECU are sensor grounds.
This schematic explains the difference.
http://www.msextra.com/doc/general/grounding.html

[kappa]

Thanks, i never really looked overly hard at that first diagram but just assumed that all the ground wires running from the ms3 where for sensors etc but in actual fact they should all be grounded to the engine? and than there are a few that i should use for sensors.

clearly i originally thought i was much smarter than i really am because i feel like i keep taking steps backwards about stupid things i have done.

thanks again guys

[kappa]

No the ones that go to Good Engine Ground.
This link.
http://www.msextra.com/doc/ms3/ls1.html
The grounds that go back to the ECU are sensor grounds.
This schematic explains the difference.
http://www.msextra.com/doc/general/grounding.html

Thanks for the second link Ollie i didnt see that until after. that clears it up!

[kappa]

Hey guys I pulled the wire pigtails on my two sensors and hooked them both up this way. Turns out I had the centre wire on the far right for both wires which might have caused a problem. Let me know if this looks correct. I didn't have the stock plugs so I couldn't tell by the wire colors

ImageUploadedByTapatalk1405255065.022705.jpg

ImageUploadedByTapatalk1405255076.421040.jpg

ImageUploadedByTapatalk1405255101.471558.jpg

[kappa]

ImageUploadedByTapatalk1405297434.412365.jpg

And the base board

[kappa]

Hooked everything up to get an rpm signal but still got nothing...

ImageUploadedByTapatalk1405302580.071942.jpg

[Matt Cramer]

For JimStim testing, what if you use 36-1 mode? The current code does not work with the JimStim's LS mode as the way the JimStim simulated the LS signal turned out to be not accurate enough to run a real engine.