What is this for?

[Ethan1990gtst]

Hi there I have a rb20det r32

Is anyone able shed some light please

I have a nistune chip in ecu no idea what tune is on it, for the loom going to the ecu they have cut 2 wires going to pin 16 and 17, they have added this little thing then put it to earth, any ideas? 

[GTSBoy]

That little thing is a resistor.

What you say about it being involved in pins 16 & 17 is hard to reconcile with reality, as pin 16 is connected to the ECCS relay (which is the main relay that starts up and runs the ECU) and pin 17 does nothing.

If I were going to put a resistor anywhere on an ECU connector, it would be to fix a water temperature (which would be both a very bad idea, and be pin 28) or across the knock sensor (with a 500kohm resistor) to fake it out if it has been removed (also a bad idea, and would be on pin 23 or 24).

But those mods would be on the ECU side of the connector. Doing it in the loom side is tres weird.

Would you care to please show a photo and sketch of the damage?

[Ethan1990gtst]

32 minutes ago, GTSBoy said:

That little thing is a resistor.

What you say about it being involved in pins 16 & 17 is hard to reconcile with reality, as pin 16 is connected to the ECCS relay (which is the main relay that starts up and runs the ECU) and pin 17 does nothing.

If I were going to put a resistor anywhere on an ECU connector, it would be to fix a water temperature (which would be both a very bad idea, and be pin 28) or across the knock sensor (with a 500kohm resistor) to fake it out if it has been removed (also a bad idea, and would be on pin 23 or 24).

But those mods would be on the ECU side of the connector. Doing it in the loom side is tres weird.

Would you care to please show a photo and sketch of the damage?

Sorry it is pin 23 & 24, and yes it is on the ecu side

[Duncan]

gold star for GTSBoy

[GTSBoy]

So there it is. It's probably a 470 kOhm resistor. 470k being a typically available size that is close enough to the ~500K resistance offered by the knock sensor. That stops the ECU from thinking that the knock sensor is absent, but doesn't otherwise do anything.

[Ethan1990gtst]

GTSBoy thanks heaps mate!

[TurboTapin]

On 7/22/2024 at 2:39 AM, Ethan1990gtst said:

GTSBoy thanks heaps mate!

If you need the OEM RB20 knock sensors and knock sensor loom, let me know. I have them both laying around somewhere.