spare output wiring

For discussing how to choose sensors and create a wiring harness for all Bowling and Grippo versions of the MegaSquirt® EFI controller.
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84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

spare output wiring

Post by 84tpivette »

just got my ms2 built and using DIYAutoTune 8ft harness, car is all wired up. My question in how and what do i need to do on board to use the spare outputs 1-4 (pins 3-6)
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

V3 board
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
DonTZ125
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Re: spare output wiring

Post by DonTZ125 »

It depends on what you WANT to do with them. The stepper controller pins have jumper pads at the processor socket, as do the CAN pins; solder jumper wires from the processor output pads to the Spare pin pads. If you plan on using any auxiliary circuits in the Proto area, you'll need to solder jumpers from the appropriate component to the Spare pads.

What are you trying to accomplish? More info in the question = more intelligent answer! :lol:
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

use the spares to switch on devices (eg fan). im using the 4 iac wire for my stepper iac. i seen the diagram on megamanual use a transistor but lost from there i see the pads on the v3 board by the db37 plug where do i get the processor output from. hope this makes a little sense. so i go from processor to transistor which is in proto area then to output pad next to db37
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
DonTZ125
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Joined: Sat May 16, 2009 1:49 pm
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Re: spare output wiring

Post by DonTZ125 »

That's basically it. See this little wiring diagram in the MegaManual; the resistor and transistor are in the proto area, then the transistor collector is wired to a Spare pin pad. The relay itself (and associated wiring, including the diode) is outside the MS box.

As suggested on the same page, you can drive a SMALL device directly from the transistor (0.6A for a 2N2222A, 1.0A for a ZTX450). Anything heavier, and you would want to take it outside the enclosure anyway to prevent noise and heating issues.
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

can the three led transistors d14-d15-d16 trip a relay if i set the relay for ground triggering or wire in new transistor
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
DonTZ125
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Posts: 337
Joined: Sat May 16, 2009 1:49 pm
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Re: spare output wiring

Post by DonTZ125 »

They CAN, but you need to be careful about the coil current for the particular relay, The LED transistors are 2N3904, and are limited to 0.2A
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

thanks just thought of another question im using a hei 7 pin distributor in my sbc what do i connect to the black wire and bare wire in the shielded ignition cable i connected white wire to pin #24 (R on hei module)
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
DonTZ125
Experienced Squirter
Posts: 337
Joined: Sat May 16, 2009 1:49 pm
Location: Scarborough, ON
Contact:

Re: spare output wiring

Post by DonTZ125 »

I'm not much up on the HEI system, but a quick check of the manual suggests you're connecting the VR sensor directly to the MS, instead of to the HEI module. Check your wiring.
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

im using this diagram Image
and wired it that way but dont show the Pin #1 used i seen another post and they grounded the Pin #1 but i dont want to smoke ms or module thanks
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
DonTZ125
Experienced Squirter
Posts: 337
Joined: Sat May 16, 2009 1:49 pm
Location: Scarborough, ON
Contact:

Re: spare output wiring

Post by DonTZ125 »

Not sure which Pin #1 you're referring to. We've reached the limits of my competence with the HEI, so I'm going to sit down and let someone else take over - as you say, we don't want to let the magic smoke out of your toys!
84tpivette
MegaSquirt Newbie
Posts: 14
Joined: Sat Nov 09, 2013 10:14 pm

Re: spare output wiring

Post by 84tpivette »

thanks alot for the help and information pin #1 in my harness is ckp- black wire in shielded wire
1984 Corvette TPI(no longer cease fire) ms2 v3 in the works
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