Problems with HFS3 RX7 install

[tommy-c]

Hi, please could somebody help me, I've installed everything on the HFS-3 and was going through the first step (pg 11 of the manual, quick start) and I don't have any response from the Gauge at all. I checked the voltage supply and grounds and they seem ok from what I can make out. I only had the power connector, grey ECU harness and gauge cable plugged in at the time

Here's how I've wired the system up, it's a later 16bit ECU RX7.



Thanks!

[Richard L]

The diagram looks 100% OK.
Can you check the voltage test pin 5.

Simple questions:
1. Is the guage button pressed down
2. Unplug the blue harness and see if it make any difference
3. Can you see any leds at all at the gauge?

[tommy-c]

I will have to check voltage at pin 5 tomorrow, could you tell me where exactly this is located?

The gauge button was pressed down
I did not have the blue harness plugged in, only power, ecu & gauge
Nope nothing from the gauge at all

[tommy-c]

I should add that I only tried the system by turning key to ignition position. I didn't get any response from the gauge so was reluctant to start the engine.

I unplugged everything from the HFS3 controller afterwards and started the engine to make sure I hadn't damaged anything

[Richard L]

I would rather you run and engine first before posting. Cannot move forward until you do the TP measuring and run the engine.

[tommy-c]

Ok I tried starting the engine and the orange light illuminates whilst the engine is cranking and then goes out once engine is started

Measurements across pin 5 are:
0.02v with engine running
0.007v with ignition only

[Richard L]

It appears the little red wire of the grey is not connected to a 12V solder and pre-crank key position.

Check the status of the IG SW (pin 40) at pre-crank key position.

[tommy-c]

I seem to only get 0.001v from that pin. I temporarily wired the red wire from grey harness to a switched 12v source and the gauge now responds as it should. Is it ok to permanently wire this instead?

Also I don't have any flicker from the green led, although I assume this is because in the rx7 the signal is from the secondary injectors, so the led would only respond when they receive a signal at higher engine load/rpm, is this correct?

Thanks for your help

[Richard L]

Make sure the switched 12V only appears with the fuel injector(+). Does the RX7 uses a resistor pack on the fuel injectors?

If it doesn't, it would be easier to wire the red and green wire of the grey connector directly to the fuel injector (+) and (-).

[Richard L]

Try ECU pin 1B for a switched 12V (B/W)