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Cant start my RB25DET R33

No spark

Have tried reading the service manual but finding it slightly confusing

I believe its the ignitor

Have confirmed voltage input with the key 'on' to 6 of the plugs (i believe one is an earth so thats fine and power is coming to ignitor)

Have pulled out the ignitor and attempted to read the resistance to every combination (one side had 6 plugs and the other 7) Have read every combination and in reverse and am getting no6resistance reading (1. on multimetre)

Did read another post here with the video where in reverse there should be a resistance reading )

Should this be right in meaning my ignitor is gone? Wierd how all 6 outputs are coming as no reading

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The ignitor is 6 transistors. The inputs to it are 1x main earth (which, confusingly, lives on the same side as the outputs to the coils) and 6x trigger wires coming from the ECU. When the ECU decides it wants to fire a coil, it pulls its output low, which switches off the transistor which removes the charging power from the coil which makes the coil discharge.

It's not something that makes a lot of sense to go measuring resistances on. The test of it's function is to manually power the inputs and see what happens to the outputs. With neither plug connected, but an earth made to pin 7 on the output side, putting power on any input should make the corresponding transistor switch on, and therefore the corresponding output should have conductivity to earth.

If you look at the wiring diagram you can easily work out where the power comes from. Power to run the coil side is connected directly to the coils, and it is this power that flows through the activated transistors to earth on the output side of the ignitor). Power to "switch on" the transistors comes from the ECU and flows to the same earth on pin 7.

Im sorry but do not really get much of it

I have put the key to on and again measured to voltage at different points

At the connector going into the ignitor im getting around 9-10v

Checking the output of the ignitor im getting 0.6v

Should i be checking while cranking?

Coil packs have 0.8ohm resistance when bench tested (should i be checking the input voltage from the harness)

On 9/27/2019 at 4:30 PM, GTSBoy said:

The test of it's function is to manually power the inputs and see what happens to the outputs. With neither plug connected, but an earth made to pin 7 on the output side, putting power on any input should make the corresponding transistor switch on, and therefore the corresponding output should have conductivity to earth.

This is the test.

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