PMU delayed power off

PMU
1

I am trying to setup a delayed power off of my PMU.
For that I would like to create a function tcombining the signal to shutdown from the ECU that I have in Analog2 with the signal from PMU pin 7 + 12v switched.
Is it possible to have the pin 7 status without using another analog entry?

2

What ecu are you using?
This can probably be done via CAN if the ecu supports it

Just so I understand the desired function, you want the ecu shutdown to turn off the PMU? what currently controls 12V to the pmu turn on (pin 7)?

3

I have a a PMU 16 that is powering a diesel Baldur Ecu that normaly needs some seconds to shutdown.
Originaly the power supply for the ecu was controled by a relay that is controled by the Ecu itself.
The Relay is powered directly from the batery thru a fuse and is controled by the Ecu
The Ecu has an entry for the 12v from ignition switch and has 1 output with Gnd that controls the relay.
How does it work:
when we cut the 12v from ignition switch the Ecu starts the power off process and when the process is done the grd output of the relay shuts the relay.
What I want is to replac e the relay by the PMU16.
The 12V on pin 7 of the PMU is controled by a switch (the same switch that controls the ECU)

4

Ahh I understand better now.

For the PMU to stay on it will need to be connected to 12V on pin 7. If the ecu’s relay control is a ground signal, it can’t keep the PMU awake. It does not have a delayed shutdown in a global sense.

You could make the PMU always on and have the switch that turns on the ecu enable power to the ecu, and another analog input for the signal from the ecu that controls the relay. In software you set it up that it holds power until the input from the ecu lifts from ground.

5

Thanks for the reply.
In fact Originaly the ECU has 2 outputs to control the Relay one with 12V and another with ground.I was only uising the Gnd one, but I can try to connect the output of the 12V to pin 7 of the PMU.

6

Connect the ignition switch signal to ECU (conn 3 pin 31) and PMU (pin 7).
Connect the PMU output to the ECU supply pins (conn 1 pin 1, 7, 8).
Connect the ECU main relay negative output (conn 3 pin 46) to the PMU analog input.

Configure analog input:
obraz

Configure delayed turn off:
obraz

How it works:

  1. The engine is running and the main relay negative output is grounded.
  2. “ReadyForShutdown” input in PMU is 0 (inactive).
  3. The ignition signal is turned off.
  4. PMU first waits the minimum time (0,5 sec), and after that, the PMU will turn off when the “ReadyForShutdown” signal becomes active or after the maximum turn off time (3 sec).
7

well I sit corrected, I didn’t know that there was a global shut off delay.
You have add a pane for it as its not visible in the default layout.

8

Thanks for the solution.
It will work for sure.
Thanks again

9

I corrected the analog input configuration to have a pull-up resistor enabled.
You need pull-up to have a high-level signal because the ECU is providing ground only.

Previously it was pull-down as default because I selected the active high switch.

10

I have tested the solution and it works perfectly.
If I remove the 12v from 12Switched (pin 7) the PMU stays ON for 3 seconds, but in the meanwhile if I remove the signal from Analog 1 the PMU shutdown immediately.
Thanks

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