Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Roadster PCB circuit diagram

Oylo, on Sunday we had the dash out with the 20A fuse for the fuse box & the 20A fuse or the dash unit out.
I rebuilt the dash & the car restarted without those fuses in.
It seems to me the immobiliser just a feed to the lights off the PCB if the engine starts.
John

The PATS LED is connected to the pcb but is wired directly back to a -5v output from the ECU (pin.42). The board contains no immobiliser functionality.

So could we infer the MIL & battery light are also via the ECU?

Yes I believe so but not directly… I am not an electronic engineer but it looks to me like they (and the temp gauge) unfortunately use secondary circuitry to interpret a data stream from the Visteon ECU. I’m guessing that is why Peter has managed to throw away his board and MFU as the Omex ECU may well handle these outputs differently

The other important immobiliser item, the transponder electronics module on the streeling column is driven by tx/rx signals directly from the ECU, so no board worries.

The Omex installation doesn't have much to do with the instruments, there is a connection which replaces the MIL light, other than that the instruments, where applicable, are still driven by the original ECU. The Omex ECU only handles engine management.

I reckon the main instruments are driven by the caerbont box?

That intercepts the ecu outputs I think?

The side lights fuse also feeds the dash lighting which would possibly tie up with Johns symptoms?

The temp gauge is the curious gauge as its driven by the ECU (i think). If there is only one resistive temperature sensor on the engine (that cannot be shared) and that now goes to an input on the Omex, the original ECU no longer knows the engine temp. So what drives your temp gauge? Have you added a second sender or is there a gauge output from the Omex?

Well spotted.

The Omex kit includes a temperature sensor that is used exclusively by the Omex ECU. It is place in the coolant tube which passes under the intake manifold, though older installations involved fitting one to the motor. This is now avoided as it would mean removing a part, drilling and tapping a hole for the sensor and then replacing the part. Fitting it in the tube is much easier



There is also an intake air temperature sensor and an optional air pressure (for altitude) sensor that is normally not required/used in the UK.

In effect the original coolant temperature sensor is now used only to drive the temperature gauge via the original ECU.

Aha!

My Module numbering on the black plastic covering is

MDE 4003 v1.13

Dash Module V6 . 4/4

236206 0710

That would infer it was different to the Plus 4 I guess?