[tx_haggis]

I need to run some additional outputs (VVT, Boost) and inputs (oil pressure) from existing connector pins to the appropriate place on the board.

What's the recommended method to connect existing unused connector pins to the board?

It looks like unused pins do not have tracks on the PCB
That leaves soldering directly to the pin(s)?
Soldering on the bottom of the board might foul the Ardiuno (esp. USB connector)?

[tx_haggis]

It's been 25+ years since I briefly soldered PCBs so for all the other noobs like me, here's what I did:

• Use solid wire
• Bottom of PCB: solder a loop round the protruding connector pin.
• For Boost & VVT
  • Route the wire directly to the correct proto pad (Boost & D44 in my case) along the bottom of the PCB.
  • Solder the wire in place from the top of the PCB
• For Oil Pressure, I went with A12 which required
  • routing the connector wire to a proto pad on the bottom
  • from the top solder another wire from an adjacent pad to pin A12
  • Finally bridge the 2 pads
• Clip all wires back
• Continuity test

Fingers crossed!

[dazq]

Just a reminder as you don't mention it.
Don't connect any additional external sensors directly to an input pin on the mega. You must ensure you add a suitable protection circuit either externally or on the proto area .
Suitable circuits can be copied from the TPS ( for a 0-5v input), or CLT/iat ( if a simple two wire resistance based sensor).

Also you should consider securing the new wiring to the PCB to prevent vibration etc effects. Hot glue or epoxy have shown good results.

[JHolland]

I think you probably didn't tin the wires before soldering because the solder hasn't flowed properly around those joints.

[tx_haggis]

Don't connect any additional external sensors directly to an input pin on the mega. You must ensure you add a suitable protection circuit either externally or on the proto area .
Suitable circuits can be copied from the TPS ( for a 0-5v input), or CLT/iat ( if a simple two wire resistance based sensor).

Uh oh! I'll get on that......

Also you should consider securing the new wiring to the PCB to prevent vibration etc effects. Hot glue or epoxy have shown good results.

Ah! My son & I discussed that, but weren't sure if it was necessary.

Thank You

[tx_haggis]

I think you probably didn't tin the wires before soldering because the solder hasn't flowed properly around those joints.

Yeah. my soldering technique is.....basic (to be polite).

Would you recommend redoing the joints?

[JHolland]

Would you recommend redoing the joints?

I would, the orange wire in the lower pic doesn't look to be soldered at all although it may have flowed on the unseen side.