PMU 16 output planning help (What can be combined)

Hi All,

I have an ECU masters PMU 16, ADU 5 dash and EMU black to be used in a MK1 escort restomod, I chose all 3 from the same manufacturers to make setup and configuration as easy as possible and the ECU master stuff seems to be great value for money and is well specced.

Having a PMU connected to the ECU and dash and a GPS module all communicating over Canbus makes wiring a control very simple and attractive to me.

I am new to wiring a complete car but pretty competent and I am working on the loom(s) now

As you can imagine I would prefer to run everything if possible from the PMU and being that it's a simple car it seems to be possible to do, even controlling the fuel pump and cooling fan through the PMU but to run everything I need I will need to combine a couple of outputs.

My question is, what is typical to combine in this situation (And acceptable), It has been suggested to me that I can combine the injector power with the ignition coil power output from the PMU together as well as the Dash power supply with the alternator field wiring

Is that acceptable, suggested?

I have attached a simple Excel sheet that I have been using to help me visualise the wiring, I have just put a list of all the pins and then added the outputs, please have a look and let me know if there is a better way to do this before I start creating this loom.

Thanks in advance

Ricky

Ricky,

For the future, ECUMaster PDM works great when combined with other brands because it has flexible CAN programming. I use them combined with other brand ECU and dashes on a regular basis, so just know that's an option in the future and it works well.

I'd put ECU+Dash on a 15 amp together, move coil + injector to a 25 amp.

That way you'll have a separate circuit available for alternator, and coil/injectors will draw more than ECU/dash generally.

In terms of lights, LED bulbs will generally be well under circuit limits, but halogens use quite a lot and may exceed your circuit limits, so choose wisely.

Thanks Mike, all understood.

Just on the lights, just a sanity check if you don't mind. The mk1 escort was fitted with the typical 7 inch sealed beam lights, I have them as 65w high beam/55w dip beam - so, 5.5 and 4.6 amps each

With this in mind, I would have the high beam circuit at 11 amps and the dip beam circuit at 9.2 amps (with the tail light 5w each, total 10.2 amps). I was going to use LED bulbs where appropriate but I will build the system to handle the standard loads.

Do the numbers seem correct? I mean it's simple ohms law but the amp draw seems lower than what I expected and a few people have told me I may exceed the 25 amp limit on the output but my basic calculation suggests I have plenty of headroom

Ricky,

2 55w halogen bulbs has been borderline on a 25 amp circuit in my experience. Some likely draw more than others. I'm not convinced they are produced or labelled in a manner that's super consistent. Fortunately if you have to swap to LED bulbs, they're cheap and work well.

Thanks Mike

You're welcome!