LS1 coils for RB platform with motec

Hi all

just needing some advice as I am stumped I am currently in testing phase of all sensors etc before firing up the engine.

i have LS1 coils and a motec m130 ecu.

I am not getting spark from coils when selecting to test fire them from the software BUT they will fire if I connect the ECU Ground wire from the coil to the shielding wire on the 3 core which is used on the crank hall sensor. Was an accident that I found that out but when hooking up to the ECU ground it won’t fire. Can anyone shed some light?

thanking you all in advance

Hi Linday,

I'm not sure what you're describing with the coil ground but I would recommend not doing it.

Coils are switched by a current source from the ECU IGN_LS resource to pos C of the coil.

LS1 coils have two grounds, pos A is the 'high current' ground and pos B is the 'low current' ground.

Technically both can go to the cylinder head if you're not sure but in the OE wiring the low current ground in B goes to the sensor 0V to ensure ground offsets don't cause the coils to trigger.

Having the Ignition Driver Firing Edge set wrong catches people out a lot, double check this is set to Falling Edge.

Have you reached out to your MoTeC dealer? they are responsible for assisting you.

Thanks Scott I will check falling edge. And yet to reach out to my motec dealer. Just thought I would try here first.

sorry if my description isn’t best I’m not one with words but I wired it with one ground to the engine and the other to the ecu 0V and had no luck with coils firing, but by accident when moving the low earth for the coil I touched on the shielding around the 3 core and for some reason this made the coils fire but the shield on the 3 core isn’t connected to anything so that got me confused hope this makes sense.

If you use the Engine Output Test function you should be able to trigger each coil, one at a time.

There's an Output Test Engine Speed parameter which needs to be a non zero value.

Also, check Engine Run State. The current sources for the IGN_LS drivers will not be enabled if the run switch is off.

Has this engine ran before switching to these new coils?

Thanks Scott coils have been used before when using a haltech platinum sport.

switched to motec and did other upgrades.

i am using the output test function to test coils.

As for the engine run state where can I locate this and is it a on/off switch I can select? I had a very quick look and could not see the engine run state.

i will hopefully address the earth wiring tonight and have an update

thanks once again

Lindsay

I attached a snip where the run switch and output test subgroups exist within the engine group of the package.

Assuming you're using a GP based firmware package.

Are you using M1 Tune 1.5? in the lower worksheet pane the startup tab has the run switch and ignition output diagnostic channels.

The Output Tests tab has the engine output test items.