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Thanks to Rich for the diagram, I think I have an idea of what's causing the problem. So yea, both the EZF relay and the fuel pump relay get power from the ignition A16, but they also get power from the alarm system wire harness as well. The LH module provides the ground so nothing special there I need to worry about. So either the ignition A16 isn't providing power or more than likely the alarm system is screwed up, assuming I read the diagram correctly. So... how hard is it to remove the glove box?
Here's a closeup with some highlights to show what I am talking about. Though Rich had explained to me that the 15 is not a fuse, but part of the ignition circuit. But either way the alarm system module is certainly the main issue.
Here's a closeup with some highlights to show what I am talking about. Though Rich had explained to me that the 15 is not a fuse, but part of the ignition circuit. But either way the alarm system module is certainly the main issue.
on my s4 the glovebox has 3 screws underneath and 1 screw at the latch.
they say the alarm control unit itself is bulletproof, it’s the sensors that fail.
I am under the assumption that if the ACU is removed and it’s connector
is jumpered it takes the sensors out of the equation.
there is a menu of oil options depending on the weather and temperatures..
many will disagree with me but plain 10w30 Castrol GTX should suffice at the moment.
on my s4 the glovebox has 3 screws underneath and 1 screw at the latch.
Thanks, that makes it much easier to deal with.
they say the alarm control unit itself is bulletproof, it’s the sensors that fail.
Where are the sensors? Not that I'll tackle that issue now, I'll wait until I have the car in my driveway to derust and clean a myriad of parts.
there is a menu of oil options depending on the weather and temperatures..
many will disagree with me but plain 10w30 Castrol GTX should suffice at the moment.
I'm thinking of using Castrol Edge for ZDDP considering this car has sat for so long, the zinc may play nicely here. Wonder why so many people seem to use much thicker oil?
For 85 & 86 its Central Electric plug pins B23 & F25 that need to be linked to re-enable the EZK/ignition.
I'm kinda concerned about the fuel pump still. The diagram shows that everything goes to this "15" which Rich says it's the ignition circuit. So is that like the ignition switch or are these all joined at some point together?
**EDIT**
Ok Rich also explained that the fuel pump doesn't get a power source from the alarm system directly, so maybe there's a dirty connection somewhere. Does anyone have a diagram that shows which connector at the bottom of the fuse/relay box gives power to the fuel pump and the EZF?
Last edited by dukenukemx; 09-01-2018 at 04:13 PM.
I think I found the problem that prevents the EZF from turning on, though I don't know if this effects the fuel pump as well. I checked for continuaty all over the place to see where the break was for the EZF. Ultimately what I did was try to find the alarm system harness which turns out was just hanging behind the fuse panel. Yea, whoever worked on this car before didn't bother to properly bolt the connector to its original placement. Also, you don't need to remove the glove-box to access it. Anyway, so I traced the yellow wire to the brown "F" connector. It was the top right most pin and there wasn't any pin. Power made it there, but there was nothing to connect to. So I said **** it, I'm removing the fuse/relay panel, and OH MY GOD. Someone had played Frankenstein with the wiring. The pin was remove and the EZF relay wire was spliced to fuse 10 and 11 along with some other wire which I have yet to trace. I'm also not sure if any of the wires in that area are correct at all. I did fix the EZF wire temporarily but I gave up and decided that I needed to take this fuse panel home and properly solder and shrink wrap the wires.
Can anyone here please give me a wiring diagram that shows where these wires are suppose to go? It's going to be hard to fix this without one. Also, this wiring job was done by a Porsche dealership in upstate NY. Not a backyard mechanic, but a dealership. The video shows the wiring job done.
Fixed what wires I saw broken and even put wires where there wasn't any. Went by the old fuse panel as a guide. I found the digram of the fuse panel but I don't understand it. Like A25 goes to connector A but which pin on there is 25? Left to right top down is how the pins are interpreted?
Fixed what wires I saw broken and even put wires where there wasn't any. Went by the old fuse panel as a guide. I found the digram of the fuse panel but I don't understand it. Like A25 goes to connector A but which pin on there is 25? Left to right top down is how the pins are interpreted?
all things considered, I wonder if reinstalling the old fuse panel wouldn’t be a better choice. ? assuming it is unmolested.
It's 100x worse in terms of molested mess. I've done a bunch of repairs so far, but I decided to clean it with brake cleaner cause it was dirty all over. The brake cleaner removed the labels on it but I'll fix that easily. I figure later on I'll repair the original panel for giggles. Maybe as a backup panel.
Originally Posted by Majestic Moose
You really ought to contact Roger at 928sRUS and get the full set of manuals.
I'm surprised no one jumped in about the oil weight, use the brand of your choice but it must be 15w-50 or 20w-50.
I think I found some errors in the diagram while checking the connections, and yes it took hours with a multimeter to check everything.
So first the diagram shows H25 -> XVIII 87, but I found it at XVII. A typo? Nothing here was tampered with.
Another one is P24 -> XI T, but it's at IX T. Because none of the wires were tampered with I assume another typo?
Last error I might have found is R21 -> KI15,Q11.12. I can't make heads or tails about this one but what I've found is the wire goes from R21 -> XX 56 -> XV 31 -> II 15 -> Fuse5 -> D11 -> VII 15 -> IX 30. This connection was tampered with, specifically Fuse5 as the person cut this wire and spliced it to someplace else. I made the repair but I wanna make sure this is correct cause this fuse goes to a lot of places. The diagram does show that D11 does go to Fuse5 as well as VII 15 and IX 30, and that all tests correct.
I also found a few relays that don't belong in my fuse panel but I'll deal with that tomorrow. I'll post pics to show what I've found.
Have you verified this is the correct panel for your model year? I would be hesitant to dismiss the wiring diagrams as incorrect, let alone that many errors.
As far as I can tell, it is the correct panel except for this big diode that I think is for the headlights. Also I checked every connection on the panel and so far everything goes where it should, with the exception of the three differences I've found. Though the old panel also has the same differences, so I doubt that's because of the previous persons muckery. Something like XVII and XVIII as well as IX and XI can be easily attributed to a typo on the diagram. It took me hours to check all the connections, which I doubt many people here have done this, so I imagine this was overlooked.
The other inconsistency was there were wires on the original panel that weren't on the new one, which I had taken off and placed them in the new one, but the diagram shows nothing should be there, so I took them back off. I'm going to double check this again, but that's kinda odd that there's wires where the diagram says there shouldn't. I really doubt the person who worked on this before actually took the time to put them in, considering how many wires were just cut and left as is, not to forget the wires he did put together were twisted. These wires looked factory.
This is going to sound nutty, but it has worked for some (a few?) people in the past when it seems like everything else is connected fine. If you replaced the CPS and the tach still doesn't bounce while cranking, either the wiring is damaged between the CPS and the EZK (ignition computer) or the tach is shorted to ground.
One quirk of the 928 electrical system is that the signal to the tach and the EZK are on the same lead. If the tach is shorted, all the current goes that way and none goes to the computer. The ignition system doesn't think the engine is turning, so none of the relays are energized.
I **** you not, people have cut the wire to the tach and their non-starting 928s have started.
09-01-2018, 01:40 AM
