I asked the question in NASIOC too and haven't gotten an answer. Hoping someone here notices and can help. I have no clue how this system works and unless someone can give me a tip, my next option is to try the dealership. Ugh. Thanks, Paul Car: '08 STi Modifications: Stage 2 with a tune from RS Motors about a month ago. Suspension, including rotors, pads, lines and brake fluid. Problem Description: Three days ago the "Hill Start Assist Off" warning light came on. (HSA system doesn't work either) I have tested every fuse and replaced the only one that was bad (for the reverse lights) which didn't fix my original problem. Recent Modifications/Maintenance: Oil change and tune about a month ago.
Thanks for the suggestion. Gave it a shot along with a slightly more complicated version I found on NASIOC. Neither worked. Any other ideas?
You can't turn off the hill assist on the 08 STI, I don't think you could turn it off until MY09, 10 or 11. Unless there is some sort of back-end hack that the NASIOC'ers found. I would suggest this:
Thanks for the tips. I have no CELs and my AP doesn't read any codes. Turns out I keep blowing fuse 18 inside my car. So I got desperate and went to the dealer. Dealer is convinced they can't fix the HSA problem until the fuse issue is resolved. They're final suggestion was to replace the main vehicle harness and dash harness. There is a wire that is jumping from .3 amps (where it's supposed to be) up to ~35 amps when wiggling wires behind the radio. I'm not ready to spend $3000 for a new wiring harness, so I think my next step is to see if I have any obvious areas grounding behind the dash.
One wiring issue clearly indicates replacing the entire engine harness and dash harness haha jk Well I hope you get it sorted out soon...I hate chasing down wiring issues lol.
Are you sure of the fuse #? I see #18 is for the back up lights. I would substitute a 3157 tail lamp bulb for the fuse. Bend the pins around so it fits for the fuse. It will current limit the circuit to 2 amps and light up bright when the short is occurring. That way you can tell when the short is happening. IE: over bumps, in reverse, with a big friend in the back seat.
Yes, I'm sure of the fuse. I put in my original post I found it bad and replaced it. What I didn't realize is it popped again as soon as I put the car in reverse. I realize HSA and reverse don't have much in common (clutch switch and reverse lock), but I'm hoping if there is something wrong with the wiring while in reverse, it may be causing the HSA to always shut off. I like the bulb idea and will try it when I get some time to dig around my car this weekend.
So I verified exactly when I'm blowing fuse #18 using the light bulb method Todd suggested. The fuse blows the moment the shifter starts going into reverse. I tested this with the key in the ON position, but the engine off. I didn't go completely into reverse either. Just lifted the reverse lock and touched the location. I tore the shifter apart inside the car and the reverse wire appeared fine. My next step, I guess, is to follow it under the car.
I would jump the wires for the R switch at the top on the transmission bypassing the R lamp switch. If the draw is ok, I would inspect the switch and harness on the transmission for shorting to the case.
