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Pull-down/pull-up resistor on aux ports?


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I have a problem with my indicator leds connected to the aux ports, i have one as CE-light and one to show when the transmission is in lock-up mode.

When the G4 ecu pull the output to ground the leds lights up bright as they should.

But when the port is turned off the leds glow very dimm.

The leds are connected with approx 900 ohms in series, producing about 18mA over the led, the manual states that it shuld be a 1k resistor, may this be the problem?


I will go over and check all grounds and maybe change the 12v source from the gauges part in the fusebox because when i use the blinkers or the reverse light goes on the ce led blink less dimm in the same pace as the blinkers or steady when in reverse.


The wiring to the leds goes through a 2wire cable with shield, 12v connected to the shield and the gorund-signals in the 2 wires.

I suppose it is possible to use relays but it feels that is over the edge to drive some leds.


Seems to be a wiring problem rather then a ecu problem ?

Is it possible to solve this using a 10k pull-down/up resistor ?






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I am currently using 2 spare aux ports, but i have 2 spare ignitions drives available. the downside with highside driving of the leds is that it will require a remake of the instrument housing which they sit in to supply ground instead of 12v+

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