MoTeC Global Forum

Hi Guys,

First time learner.
This may be a stupid question but thought I would ask because I can't find the answer.
I have a PDM16 and am just starting the test wiring to figure things out. Can you wire your injector loom to the PDM or does it have to be directly to the ECU.

I have never used a PDM before so this is a massive learning curve for me.

Thanks

Hi Hello,
Yes, you can wire the injectors to the PDM.
You should be wiring it in such a way that the injectors get +12v from the PDM and the ECU provides the low side to them.

I should add that generally the only devices that need to be wired to the ECU are stepper motors or DBW motors etc (generally using the half/full bridges).

Hi,

As Ryan stated, for Port Injectors you wire the injectors so that they are supplied BattV+ by the PDM, and are then low side switched by the ECU to ground to trigger the injection event.

With a Direct Injection engine however, the Signal+ and Signal- for the injectors is provided directly by the ECU, as these injectors require a higher voltage to be driven than can be supplied by the vehicle charging system directly. The DI ECU's have built in control systems that are designed to drive either piezo or solenoid type DI injectors.

Hi Guys,

Thanks for the help. I really appreciate it.

SDean wrote:Hi,

As Ryan stated, for Port Injectors you wire the injectors so that they are supplied BattV+ by the PDM, and are then low side switched by the ECU to ground to trigger the injection event.

With a Direct Injection engine however, the Signal+ and Signal- for the injectors is provided directly by the ECU, as these injectors require a higher voltage to be driven than can be supplied by the vehicle charging system directly. The DI ECU's have built in control systems that are designed to drive either piezo or solenoid type DI injectors.

rntechnologies wrote:I should add that generally the only devices that need to be wired to the ECU are stepper motors or DBW motors etc (generally using the half/full bridges).

Thanks for the help guys. I really appreciate. I have come to the conclusion I should probably let the pros wire the engine loom. I think i may restrain my learning to the accessories loom for now until I am confortable