Chasing CAS Wires at ECU

[mosquitocoils]

Bit of a strange one here but I am trying to identify which are the correct CAS wires at my ECU.

(My S1 Stagea has the 0v300 ECU for which a pinout is basically non-existent. Some wires match with the R34 GT-T ECU but some do not, most importantly the CAS wiring for Home and Trigger. I'm trying to wire in a Haltech Elite 2000 and I'm stuck on these ones.)

I'm a bit of a noobie when it comes to ECU wiring I will admit, but I have a lot of history with general car electrics. I thought this would be a simple case of unplugging the CAS plug, sticking a wire into it, running the other end of that wire into the cabin and checking for continuity between that and any/all of the ECU plug pins. When I did this I couldn't get any continuity readings from any of the 4 CAS pins across every ECU pin.

I'm thinking I might have over-simplified the process and hoping someone here could help confirm a couple of things:

- Where do the wires from the CAS actually go before going to the ECU? From the overall R33/R34 wiring diagrams it looks like it should be a straight connection. between I notice one of the colour of wires at the CAS plug do not show up at the ECU at all (peach) and the 2x thick green wires which are meant to be the CAS Home signal at the ECU are not present at the CAS plug itself either

- Does the ECU have to be plugged in to get a continuity signal? I.E. me unplugging the harness could have interrupted the signal? Do I just pierce the back of each wire with my multimeter probe?

- Same question for the CAS itself - does it need to be plugged in?

Thanks

[robbo_rb180]

What cas do you have metal or plastic? As they are reverse of each other 

Need sensor gnd, 5/8/12 volt (ecu dependant, trig 1 to cam(home) , trig 2 to crank

 

[mosquitocoils]

Thanks mate. Interesting that you said it needs sensor ground to crank. That would probably indicate that the ECU harness would need to be plugged into the ECU for my testing as the sensor grounds all come together there don't they? Might have to get some better probes that can better pierce wire insulation.

I have the metal Mitsubishi CAS... and I've looked at that diagram A LOT over the past few days but it doesn't help me identify the specific place on the ECU the wires come out. That's why I'm trying to check continuity of wires between CAS plug and ECU to figure out which one is which manually. I was hoping there was an easier way but it doesn't look like it.

[mosquitocoils]

Also I identified a gnd and a 5v pin at the CAS plug. The other two pins weren't giving my any voltage drop to ground.

[robbo_rb180]

The trigger wires you need the 12v, gnd and the trigger + of each to the trigger 1&2. 

It may seem confusing as there is separate wire for cam and crank with all the wires as most people go to a full trigger kit but if you look at the diagram power and ground are the same pins at the ecu

[robbo_rb180]

Are you running a whole new loom or using the factory Nissan loom? 

Use the link ecu help file for factory ecu pin out at factory ecu side but easy enough to find with multimeter from cas to ecu

[KiwiRS4T]

3 hours ago, mosquitocoils said:

Bit of a strange one here but I am trying to identify which are the correct CAS wires at my ECU.

(My S1 Stagea has the 0v300 ECU for which a pinout is basically non-existent. Some wires match with the R34 GT-T ECU but some do not, most importantly the CAS wiring for Home and Trigger. I'm trying to wire in a Haltech Elite 2000 and I'm stuck on these ones.)

I'm a bit of a noobie when it comes to ECU wiring I will admit, but I have a lot of history with general car electrics. I thought this would be a simple case of unplugging the CAS plug, sticking a wire into it, running the other end of that wire into the cabin and checking for continuity between that and any/all of the ECU plug pins. When I did this I couldn't get any continuity readings from any of the 4 CAS pins across every ECU pin.

I'm thinking I might have over-simplified the process and hoping someone here could help confirm a couple of things:

- Where do the wires from the CAS actually go before going to the ECU? From the overall R33/R34 wiring diagrams it looks like it should be a straight connection. between I notice one of the colour of wires at the CAS plug do not show up at the ECU at all (peach) and the 2x thick green wires which are meant to be the CAS Home signal at the ECU are not present at the CAS plug itself either

- Does the ECU have to be plugged in to get a continuity signal? I.E. me unplugging the harness could have interrupted the signal? Do I just pierce the back of each wire with my multimeter probe?

- Same question for the CAS itself - does it need to be plugged in?

Thanks

OV300 is the most common ecu

pin44/45 trigger1

pin46 trigger2

earth can be anywhere e.g.32

[mosquitocoils]

20 minutes ago, KiwiRS4T said:

OV300 is the most common ecu

pin44/45 trigger1

pin46 trigger2

earth can be anywhere e.g.32

Thanks Kiwi. I was so sure that the 2x CAS 120 wires I needed had to be green as per the excel doc floating around, that once I saw them I decided they were it. Circled in pic attached.

I see now that I was a whole block away from where I should be looking... and the fact they weren't next to each other, but on top of each other was making me think my wiring was all messed up... the black/red wires next to each other (44/45) and the and peachy wire (46) do look correct now. I'll splice into them when I get a chance and report back. Thanks!

I'm still unsure how to test continuity though (just for future things like this) and I'm gonna keep trying to verify as I feel it's a pretty handy skill to add to the list!

Ya live, ya learn ?