Sorry if this doesn't make much sense, I am at work away from the car and just planning some things for later.

I am in the process of wiring up my LS6 using a PSIconversion standalone (HAR-1017) and chassis using a Painless harness (20104 28 CIRCUIT). I want to retain the BMW ignition switch and key. I am planning on cutting the pigtail off the BMW harness and then simply soldering the wires to the BMW connector.

The PSI harness has a RED wire marked IGN FEED that wants 12v fused switched power with key on and cranking.

The painless harness is as follows

IGN START - 919 - PURPLE
IGN COIL - 913 - PINK
ACC FUSE PANEL - 932 - BRN
IGN SWITCHED FUSE PANEL - 933 - ORN
BATTERY B+ - 934 - RED

Now, I am pretty sure the starting is handled by the PSI harness, as it has 2 large ring terminals that connect to the starter (BAT) but I don't see any starter signal wire in the PSI harness.

I am pretty sure I just omit the IGN COIL wire as the coils are controlled by the PSI harness as well.

Do the BRN and ORN get connected together? (I don't care about the ACC function working) Then the BRN/ORN and the RED from the PSI harness all 3 get connected to the 12v out (on and cranking) of the BMW ign switch?

Is BATT B+ supposed to be the 12v IN to the igntion switch?

Sorry, wiring is not my strong area.

thanks

 

The PSI harness does not have a wire for the starter solenoid itself, I had to run a wire from the ignition switch to the starter on mine, for your application it would likely be IGN Start - 919 - Purple. If I remember correctly for the wiring I did last time I used a Painless harness that's correct. IGN Coil - 932 - Pink shouldn't have a use in this instance. ACC Fuse Panel - 932 - BRN and IGN Switched Fuse Panel - 933 - ORN and PSI Red could all be connected to switched 12 V if you wanted.

Battery B+ - 934 - Red just needs to be hot at all times, the 12V feed to the ignition switch would likely work for this.

 

Thank you!

The PSI harness has 2 large ring terminals that are STARTER (BAT +) but I figured out they are actually taking power from the starter lug back and is the constant power source for the ECU.

When you did the painless harness, where did the 12v source come in to the fuse box from? and how did it get to the IGN switch? Sorry, the painless harness instructions aren't very helpful

 

Oh, I also found this "To supply power to a fuel injection system, use ENGINE SECTION A wire #920 (pnk) as the fused ignition power
source."

 

I've used two painless harnesses, with one I had wired the main power cable (00 GA) to a main distribution block which is what I used for power distribution to constant power sources like the one that would feed the Painless harness Battery B+ wire. The other one I used the more common method of hitting the power lug on the starter similar to the PSI harness. This is a fairly high draw circuit, you want a somewhat heavy gauge wire for this and from what I remember the Painless harness uses a 10 or 8 gauge.

You are correct that the two ring terminals are a constant power source, the reasoning behind hitting the starter is it's an easy way for a guaranteed direct battery power source with proper gauge wiring to handle load.

Now, as far as the ignition switch goes I need to clarify on what I said earlier while expanding to answer the question of what feeds it. 934 is the constant hot feed IN to the ignition switch, as you alluded to originally. This constant hot is fed within the Painless harness from the main battery feed that is landed either at the starter or battery which should be labeled 916 according to the documentation I have. I don't recall what all is between the starter terminal and switch as far as within the harness but I don't recall it being anything that needs to be terminated by an end user. I'm fairly certain it is just the constant hot section of the fuse block for things like lights, horn, etc.

 

Thanks so much. I was way lost, but I think It makes sense now.