Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

thats what I get. My reading gives me .7-.8 when you said close to zero

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

Thanks for posting and help with the connections.

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

no problems!

so Chris - can you confirm that:

with the gauge OFF =
OMH meter between white and black shows around 1 ohm (ie some continuity)
OMH meter between white and brown shows 0.L (ie no continuity)

with the gauge ON =
OMH meter between white and black shows 0.L (ie no continuity)
OMH meter between white and brown shows around 1 ohm (ie some continuity)

if thats the case then:
1) reconnect the white output back to the ECU pin (ie where you had tapped into before - you had cut the existing wire obviously because your ECU was reporting that the fuel temp sensor had an error)
2) connect black wire to a 250ohm (ish) resistor, then then the resistor to ground.

quick explanation:
When the ECU sees the voltage go ABOVE the threshold (ie no continuity condition) it will start the timer to swap to alternate maps.
When the ECU sees the voltage go BELOW the threshold (ie some continuity) it will INSTANTLY swap to normal maps.

Lastly is DHB linked or not?

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

Yes I can confirm all the above. I see .7-.9 when i get continuity.

I will reconnect everything. I have the resistor soldered onto that ground wire already. This is exactly how it was wired after I changed it from the brown wire to the black wire.

I have DHB linked.

So if it still doesn't work, my ground wire/resistor has an issue? I want to say I used a 220 ohm resistor.

I will report back. Thank you for all your help

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

if it doesn't work, then log 0x80500A (2byte) and we will see what the ECU is seeing...

it may be that the ground you have isn't the best and so there is some extra resistance in play, so we might need to adjust the crossover value..

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

Try to use a ~100ohm resistor. (connect the 270 & 220 in parallel). This will bring the ground voltage even lower when black is grounded.

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

Ok, so I checked and I used a 4.7k ohm 1/4w resistor. Will this work or do I need to get a different resistor?

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

4.7k resistor is not going to work at all, you are going the wrong direction. Can you try it the way I suggested. You are just making thing more complicated.

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

Thanks Richard. A friend gave me the open pack of resistors and stated they were 250'ish ohm. Since there was no label on the pack anymore, I had to google the part number and found the mistake. I purchased a new pack of the 220ohm yesterday and installed it. Everything was working but opposite of what it was supposed to do. Tephra told me to switch back to brown as the ground wire instead of black. Now everything works as per design. Thank you both for your help and looks like the drawing was correct afterall and brown is correct.

Re: Mitsubishi EVO (USDM) wiring diagrams for HFS-3 (all US models)
 

More work for me to re do the diagrams again.