Information on my wiring setup
Tachometer (RPM Rev Counter)
Original setup
Originally the rpm signal is feed from the coil (-) (Single coil distributor) to the fuse box where the signal is distributed to the fuel pump relay, multi function instrument (shift light for economic driving, fuel consumption calculations) and tachometer.
New setup:
I'm now using 4 COPS and need a new tachometer signal and rpm signal to the fuel pump relay.
A possible solution is to wire signal from each coil with separation diodes into the cars original wiring
Using 4 high-voltage diodes (such as ES2J or BY399 or even 1n4007) to make a tach signal compatible with the original sounds good.
A similar solution is described at the bottom of this page http://www.megasquirt.info/ms2/EDIS.htm
Questions from others:
Why don't you control the shift light and fuel pump relay directly from the ECM ? To keep it simple I prefer to use a well known solution at the moment (and it's simple to wire in one cable)
Pin-out
work in progress
| Function | Wire Color | VEMS ECU pin | Car & Unit pin | Comments |
| Vbatt | ? | EC36-25 | Only power when ignition_on | |
| Ground | ? | EC36-26 | Connect as close as possible to the chassis ground / engine | |
| Power Ground | ? | EC36-21 EC36-32 EC36-5 | Connect together in the wiring and ground to chassis or engine | |
| Trigger | ? | EC36-27 | OEM 60-2 wheel on crank with sensor 90 deg before TDC | |
| TPS | ws/ge | EC36-1 | Pin 5 TB | |
| Coolant temperature | ? | EC36-14 | ||
| Manifold air temp | sw/ro | EC36-2 | Pin 1 AIC | |
| Fuel pump relay | ? | EC36-17 | (29) on Relay | - |
| Injector 1 | ? | EC36-7 | Pin 2 Jet | INJFET_1 |
| Injector 2 | ? | EC36-19 | Pin 2 Jet | INJFET_2 |
| Injector 3 | ? | EC36-8 | Pin 2 Jet | INJFET_3 |
| Injector 4 | ? | EC36-20 | Pin 2 Jet | INJFET_4 |
| Idle controller | ? | ? | ? | Will use one of the Injector channels |
| Ignition 1 | ? | EC36-33 | Pin 1 Coil Cyl 1 | Pin 15 (+) fused 20A Pin 4a (-) |
| Ignition 2 | ? | EC36-34 | Pin 1 Coil Cyl 2 | Pin 15 (+) fused 20A Pin 4a (-) |
| Ignition 3 | ? | EC36-35 | Pin 1 Coil Cyl 3 | Pin 15 (+) fused 20A Pin 4a (-) |
| Ignition 4 | ? | EC36-36 | Pin 1 Coil Cyl 4 | Pin 15 (+) fused 20A Pin 4a (-) |
| DDFlyBack | ? | EC36-23 | Wired internally grounded as close as possible to the chassis ground / engine | |
| WBO2 heater- | ? | EC18-18 | Pin ? WBO2 | |
| WBO2 nernst | ? | EC18-13 | Pin ? WBO2 | |
| WBO2 pump- | ? | EC18-7 | Pin ? WBO2 | |
| WBO2 pump+ | ? | EC18-9 | Pin ? WBO2 |
You may find:
http://www.vems.hu/wiki/index.php?page=MembersPage%2FPhatBob%2FUserGuide
Helpful
More info will come shortly