Hi All,

Recently I've made the jump from my JDM ROM 88570008 to Tephra V7 88592715 on my JDM Evo 9 MR. Everything went fine and i'm almost finished with fine tuning the car except one CEL:
P0462 Fuel Level Sensor Circuit low input

I believe the USDM ECU receives fuel level information through pin 95 & 97. For JDM ECU, these pins are empty. Studying the manual, I've connected the required sensors to these pins but the code is still there leading me to believe the JDM ECU internal circuit might be different.

I've also tried disabling periphery bit 11 (FDA) without any joy.

My understanding of the diagrams can be found in the attachments. For a more detailed diagram, I'm linking the PDF I've created below:
https://bit.ly/2YZK5aZ

I'm out of ideas...any suggestion will be much appreciated. Thanks in advance.

Fuel Level Sensor Diagram

EVO 9 ECU Pin Variations

 

It looks like you need to move pin 51 (JDM fuel level sensor input) into position 95 for the fuel level input your USDM ROM is expecting.

 

Thanks for the suggestion cdrinkh2o, but I believe pin 51 is baro input for JDM 9. Attaching the ECU pin diagram for reference.

 

My mistake. It's actually pin 51 on C108 (see page 2 of the pdf) into the instrument cluster. You can splice into it to feed pin 97 on your USDM ECU. You will also need to splice into D28 pin 2, between the two fuel senders, to feed pin 95 on your ECU. These should give you the voltages that the ECU is expecting to prevent the P0462.

 

I believe D28 (2nd page of PDF) & D10 (1st page of PDF) refers to the same connector (Fuel Level sensor - Sub)?
My initial plan was to connect these 2 lines to pins 97 & 95, but i noticed that Pin 1 from D10/28 goes to combination meter C108 (pin 51). So,out of laziness, I didn't tap the wire from behind the combination meter, rather, connected Pin 1 & 2 of D10/28 to ECU pin 97 & 95 which didn't solve the problem.
Do you think connecting C108 pin 51 in place of pin 1 of D10/28 will make a difference?
On a side note, adding "OBDII circuit test bypass" code to XML and changing hex to 0x9 seems to have solved the problem, but I ran into car stalling with AC on and clutch in. Not sure if its a direct result of disabling OBDII circuit, as I didn't get the time to revert back to enable OBDII circuit and drive the car.
This is the code i added to XML: <table name="ODBII Circuit Test Bypass (Stock 0x4A0B -> NOP 0x9)" address="11642" type="1D" level="1" scaling="Hex16"/>

 

Fixed the AC on clutch in while driving stall problem by adding below to XML and adjusting tables accordingly:

<table name="Decel Fuel-Cut Fuel-On RPM v Temp" category="Decel Fuel Cut" address="3030" type="2D" scaling="RPM8">
<table name="Coolant Temp" address="6fde" type="Y Axis" elements="8" scaling="Temp"/>
</table>

<table name="Decel Fuel Cut Resume RPM" category="Decel Fuel Cut" address="30fe" type="2D" level="2" scaling="RPM8">
<table name="Engine Temp" address="6fde" type="X Axis" elements="8" scaling="Temp"/>
</table>

It had nothing to do with disabling circuit bypass: <table name="ODBII Circuit Test Bypass (Stock 0x4A0B -> NOP 0x9)" address="11642" type="1D" level="1" scaling="Hex16"/>

I haven't been able to test if the code P0462 comes back with OBDII circuit bypass activated. Will be testing and updating soon.

 

Update on P0462: This has solved the problem.
<table name="ODBII Circuit Test Bypass (Stock 0x4A0B -> NOP 0x9)" address="11642" type="1D" level="1" scaling="Hex16"/>

Cheers!

 

Hey man did you mean 88590715? I wasn't able to find any listing for 88592715 but I did find some others suggesting in another thread to use 88580714 for the JDM Evo 9.

 

Hey brother could you re-upload a link to that ecu pinout for the JDM Evo 9 ECU? Or email it to me if you would prefer.

 

I'm using 88592715 which is 3D VE ROM for the 8859 variant. 88590715 is for cars using MAF.

 

Here you go...

 

roger my bad i should have updated my post. This was from awhile ago but i figured it out.

 

appreciate it brother!

 

I still haven't figured out a suitable way to turn off the P0462 code for 8859 rom used on a JDM IX. Turning on "ODBII Circuit Test Bypass" turns off all CEL which I'm not very comfy with.

Please keep me posted if you figure out something. I think the best way would be to dig out the MUT address for this code and turn it off. But so far all my searches have turned up empty :-(

 

Yeah so I just sent it to my tuner and he was able to disable it. He's here on the forums so lets see if he's willing to comment on it. @Boosted Tuning