MoTeC Global Forum

Hello,

How would i set up the PDM to activate a spare plumbed in fuel pump output in case one of these scenarios might come up while on track ?
Pump shorts out and the PDM output goes into protection after several retries , overdraws current , does not draw current .
I have attached configuration file .

Much appreciated,
Adrian

Hi Adrian,

You have you lift pump on output 6, your main pressure pump on output 7, where is the backup lift pump wired to ?

All of your outputs are assigned.

Hi Nathan ,

I had some issues filling up the surge tank by a Walbro pick up pump during a race and decided to eliminate the pick up pump and surge tank and have the engine supplied by the main pump Bosch044 directly from the fuel bladder. It worked fine and now decided to add another bosch 044 . I will be adding a fused B+ from the battery as i ran out of 20 amp outputs from the PDM to a relay that will be controlled by the pick up pump output of the PDM.

Adrian

So to follow this:

+ your pick up pump is removed, so this output is no longer used.
+ You are now using the fuel pump output for your Bosch 044

Why do you require a relay and are out of 20A outputs? Why does the second 044 not get wired to the pick up pump resource? Bosch 044 pumps only draw around 14 amps at 72psi.

The pick up pump was connected to an 8 Ampere output which will not be sufficient for a 044 + the wire gauge that I have run to the pick up pump i believe will not be good enough for a 044.
I could swap pins at the PDM with another circuit that does not require a 20 amp protection output and run a proper gauge wire to eliminate the relay install .
My question is how would I configure the PDM to have the second pump( back up) start in case the main pump fails , draws too much current , output retries etc.
The fuel system has fuel pressure sensor wired to my dash2pro . I could have its value transmitted over CAN .

Hi,

You can use a True Operation using the FUEL_PUMP.Status channels as an Or statement in the Output Condition for your secondary fuel pump, this will activate the output if any of the selected FUEL_PUMP fault status channels go True.

To get some Outputs back, you could merge the Coil and injectors to the same output, and the CAM sensors onto the Oil Level or ECU power.

nybimmers1 wrote:The pick up pump was connected to an 8 Ampere output

Your attached config has your pick up pump attached to output 6 - which is a 20 AMP output