Hey,
I have a blow fuse under the hood on my 09 TL awd and it says on the cover " FI sub" 15amp fuse. What does FI means? I lost my awd and ecu is giving me a bunch of codes.


thank you
Step

 

FI = Fuel Injection = part of the full acronym PGM-FI = Programmed Fuel Injection

Fuse 14 is "FI Sub", because it's the fuse for the PGM-FI subrelays as well as other stuff:

Doesn't seem to control anything specifically SH-AWD related. What codes are you getting? Any specific error messages popping up on the gauge cluster screen?

 

Thank you , Very appreciated

 

Riboflavin thank you for your reply , I had to put this issue on the side and now i am working on my car now.
Codes are 1035, 1055 and 0498 my FI sub fuse burns out and my sh-awd light is on .

I change one O2 sensor replace the 15 amp fuse clear my code and i was good for 3 days, On the third day i went for a drive stop for 20min then when I started the car all code came back and sh-awd light and burnt fuse. So i replace the other O2 sensor thinking it was the heater that was the problem. The same thing happen after 2 days burnt the fuse again .

I notice that when i put the fuse in you can hear a relay click on .

what else that fuse is used for ? Mitchell on demand it's not very helpful to diagnose the problem .


thanks

 

you're treating the wound, when you need to treat the symptom.

B1055 ACURA Description
The Relay Control Module monitors the Multiplex Control Unit Module (MICU). The Relay Control Module sets the OBDII code when the Multiplex Control Unit Module (MICU) is not to factory specifications

something is shorting out the multiplex unit


even if you replace the multiplex unit, the problem may still come back unless you find what is causing the short

 

justnspace, sorry all codes are P1035, P1055, P0498 not B1055

 

very unlikely...P-codes start with 0. for example P0xxx
furthermore; googling p1035 doesnt bring anything up except for VVTI error, which that's a toyota thing...we have have variable cam timing as well, but it's called VTEC.
However, googling B1055 brings up a multiplex unit error, which falls in line with your fuse problem..because the multiplex unit controls everything.

you have a faulty MULTIPLEX unit, but what caused the unit to short/fail?

if we go back to the 2nd post and look at the fuse description;



#14 controls the multi-port fuel injection relay.
Nothing to do with variable cam timing.

 

perhaps a bad battery can set off these codes; as there isnt enough voltage to operate the electronics

 

what was the result of your findings?

 

Also a heads up on the SH-AWD part ai didn't read. Your car will always go straight to FWD if any engine errors pop up for safety reasons. Less power means you can't distribute to both front and rear so rear shuts off and all power to the front for reliable driving to a safe location.