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As you can see from the instrument cluster picture a few post up, both the airbag and ABS/PSM lights up for error. Started to tackle this yesterday.
Changed out the ABS control module, its located under the dash, just infront of the shifter
Cleared the codes - only one error left, since the pedal values goes to the LS7 ecu, and not the Porsche. Guess PSM may still light up, while ABS will be ok? Will dig deeper into this later.
Changed out the broken Airbag Module, reset the errors and started to look promising:
Missing the passenger side airbag, which I need to move from another car, or just put in a resistor to trick the system.
Using a Durametric as diagnostic, but also got a PST2 - the original Porsche tool - which can do a bit more magic, but slow as hell (Runs on a 486 laptop!)
Stuck at work, so thinking about the pedal signal for the porsche ecu. I got an extra porsche pedal sensor, so I think I will wire this up to the porsche ecu - then the errors should be gone, but the porsche ecu will always think it has zero throttle input.
I wonder if there is logic built in to throw an error when you have forward thrust (say rams off idle, even) and no throttle input. I'm thinking at least traction control might not like it.
Worth a try, still, of course.
Did you map and connect the LS7 pedal position sensor to the analogous Porsche wiring?
Does the Motec computer allow you to use different pedal position sensor resistor values as inputs? If so, maybe you could map the Porsche resistor values to the pedal position input?
Hope my suggestions make sense. Guessing you already tried some of that.
Doug
I wonder if there is logic built in to throw an error when you have forward thrust (say rams off idle, even) and no throttle input. I'm thinking at least traction control might not like it.
Worth a try, still, of course.
Did you map and connect the LS7 pedal position sensor to the analogous Porsche wiring?
Does the Motec computer allow you to use different pedal position sensor resistor values as inputs? If so, maybe you could map the Porsche resistor values to the pedal position input?
Hope my suggestions make sense. Guessing you already tried some of that.
Doug
I would prefer if the PSM (traction control) didn´t interference, but I needed to get rid of the error message!
The Porsche Pedal position sensor wires straight into the LS7 loom, both using 0-2.5v + 0-5v for throttle position.
Im not running a motec computer - just for power distribution. But made progress today, will make a new post now!
Porsche pedal position sensor, made by bosch. The color of the wires are of course not the same as Porsches harness which it connects to, so needed to figure out what was what!
Green = Green/white
White = Green/Grey
Grey = Red/Purple
Brown = Green/Black
Pink = Green/Yellow
Yellow = Green/red
This is my current wire setup. Should be able to clean out much later on, but that would be next stage!
So, started to work on the error codes. The ABS/PSM showed no fault as soon as the porsche pedal sensor was connected, and errors reset.
Had three airbag error - one airbag missing and for both belt buckles. Sorted the missing airbag and passenger belt bucklet easy, but the drivers bucklet still gave an error. Removed the seat, and woundered why one of the ground cables hided under the carpet..
Clean dash! (Last red light are just the hood that are open)
Ended the night with just tighting a bolt, since I had a very small oil leak around the porsche oil pressure sender - bolt snapped Oh well, thats something to fix tomorrow then!
A bit of color concept - as the car original had savannah interior, and I hate anything else than black.. So all bits I was missing - has been bought in black! Will change the dash one day, but not very high on the priority list at the moment...
great progress !
so to get the abs and psm light to go out all you had to do was basically connect the ABS module and TPS sensor?
Thanks!
Thats right, only fault I had in the end on the ABS/PSM was signal from the TPS. Hooked up the one I had as spare, zip tied it in place with the P-ECU, reset the error codes - and voila! Error gone!
PSM won't care about forward movement and no throttle I'm betting. The standalone in my 996 doesn't allow the PSM to control throttle but it can still handle braking the individual wheels - no lights. Nearly certain there's an accelerometer in the system btw.
Curious, how hard is that pedal sensor to replace? My pedal is fine to about 9% TOS and then seems dead before suddenly jumping to 14%, smooth otherwise. It's annoying! Congrats on scoring the Porsche diagnostics, I'd love to have that myself! Source and cost?
The 996 uses a few more analog gauges than the 997, that one has far more CAN onboard. Have you put a limited slip in the transmission yet? If not you'll want to consider it, AWD guys going to 2WD claim the wheel spin is pretty bad and hopped up AWD guys find that too. If you've not converted to 2WD be sure to pay attention to tire height, front wheels need to be taller than rear to get power transfer to the front - it's a fairly crappy mechanical system using viscous fluid. The 997 electronic front diff bolts in but obviously has to be controlled to work...
Lastly, PSM cannot simply be turned off. It will reenable itself if it feels things have gone "bad". Guys who track 996 disconnect it in the frunk and some even install toggles to make it easier - you'll get lights though.
Curious, how hard is that pedal sensor to replace? My pedal is fine to about 9% TOS and then seems dead before suddenly jumping to 14%, smooth otherwise. It's annoying! Congrats on scoring the Porsche diagnostics, I'd love to have that myself! Source and cost?
Think it should be pretty easy to change, but if you are tall like me, its not very comfortable to do things under the dash... I'm using Durametric for diagnostics: http://durametric.com/
Originally Posted by BLKMGK
Have you put a limited slip in the transmission yet? If not you'll want to consider it, AWD guys going to 2WD claim the wheel spin is pretty bad and hopped up AWD guys find that too.
As I am using the G96.88 - transmission from a 996 GT2, limited slip are standard - but the standard LSD unit wears fast, so think it will be limited how good it works - rebuild one day! This is also a RWD only transmission, so no AWD.
Originally Posted by BLKMGK
Lastly, PSM cannot simply be turned off. It will reenable itself if it feels things have gone "bad". Guys who track 996 disconnect it in the frunk and some even install toggles to make it easier - you'll get lights though.
At the moment, no lights are the most important thing - to get it road legal here. A failure (light) on a safety system are a no go to get it approved. I also got a 996 GT2, with no PSM - prefer to be in charge myself!
I have a Durametric but some modules supposedly only respond to the Porsche stuff, thankfully I seldom need it
That trans is a good one, I'd love to find one or a 997.2 trans, not sure the .1 are any better than what I have. That LSD likely won't last too long but it's better than the open diff I've got! I suspect a Wavetrac will wind up in mine and perhaps a billet cover, I sure don't want a rebuild anytime soon! Unless I find a 997 front diff I'll likely end up RWD as well with as little help I get up front now. Even RWD though you can apparently have issues with the PSM and possibly ABS freaking out over tire sizes, not sure how you can best solve that. It's a shame no work seems to have been done flashing these ABS, the CUP stuff is supposed to be better but no fun to install. "Ice Mode" is apparently an issue at the worst times on track.
Sounds like you have most of the lights solved though! I bet a proEFI could run both the V8 and the CAN stuff if you wanted but obviously plug-in emissions wouldn't work if you have to deal with that
07-10-2016, 03:00 PM
(Last red light are just the hood that are open)
Oh well, thats something to fix tomorrow then! 
