2015 Allroad completely dead! Help :(

[beezie84]

I bought my first Audi after 18 years of BMW ownership. Picked up a 2015 Allroad with 130k about a month ago, had the timing chain work done right when I bought it. During the first couple of weeks the "parking brake malfunction" warning popped up 4 times. Twice it just flashed and went away and two other times it came up when I put the car in reverse and it cut the car off while in gear but both time I was able to restart it within a minute or so. Last Friday right before a planned 4hour trip to Ottawa it happened again when backing out of my parking spot and the car went completely dead. I still had power to things like the interior lights but that's it, I waited about 15min and still couldn't get it started... I disconnected the battery for a few minutes reconnected and nothing. After another 10-15min of frustration power magically came back on and she started up like normal. Stupidly I decided to risk it and do the 4hour trip to Ottawa, after stopping 3x (for gas, food, and my first destination) everything was fine no issues. I parked the car at the motel for the night and I came back out 30min later to get something from the car and noticed the key fob wasn't working. Everything was dead again power to interior lights but nothing else. In the morning I went and picked up a new battery and swapped it out did not solve the problem. Had to pay an expensive tow to the dealership closer to home. Any idea what this could be?? I messaged the previous owner he said that something similar had happened to him 8 months prior and the dealership just reset it for him but never gave an explanation. The battery looked like it was the original so it was at least 7 or 8 years old, but voltage seems fine.

I'm completely stumped by this and now I'm at the mercy of the stealership.

Any ideas please!!!

[maRS5]

The only time I've ever gotten a parking brake malfunction error was when I was changing a part on my center console (the part where the shifter/MMI controls are) and I hit the start/stop button while the e-brake switch was still unplugged. Maybe could it be a bad e-brake and/or start/stop button switch? Might be worth it to pop off the center console to see if there's any frayed wires or maybe buy some used switches and swap them out to see if that solves the problem. Low cost and not difficult to do (plenty of youtube videos on how to do it). The only other guess would be that whatever control module associated with those switches/ignition might be bad.

[Smac770]

It's near impossible to speculate electrical issues without starting with a full scan to get some idea of where all the issues seem to be located. Anyone owning an Audi should own VCDS, but people seem to like other tools as well. So long as you can produce a VCDS caliber full vehicle scan log to post, doesn't really matter what tool you use. But you're going to need something, or be prepared for a more expensive and inconvenient than necessary ownership experience.

https://store.ross-tech.com/shop/vchv2_ent/ (direct Canada sources - https://www.ross-tech.com/distributors.php)

OBDeleven apparently has added BMW support now, if you're still a dual make household. But is a pita to use for troubleshooting, imo, and requires a $50/yr subscription to enable all the functions you just get with VCDS.

[mrg_B8TFSi]

Agree… need a full system and all modules scanned.. if there’s some faults and it seems this is an intermittent fault.. VCDS “Ross tech” software is needed. Like mentioned there are other scanning tools but VCDS never has issues with VIN identification or module compatibility.. something is intermittently creating a fault or interference with ECM and it’s shutting down all power.. this is a needle in a haystack situation without knowing what module or relay to look at.. but it’s something that is resetting itself.. most likely a sensor, I don’t know of anything in the EPB circuit that would create a system power shutdown like you’re describing? I think that EPB fault is a by product or it’s possible you have a bad electrical motor “probably someone did rear brakes without proper scan tool” and with a faulted brake motor it’s causing power problems.. use VCDS to cycle the EPB a few times to maybe reset? Maybe there is a limit switch on the motor to provide feedback to the ECM that EPB is working and clear of the caliper? Just thinking out loud


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[eljay]

Well, since it's at a dealership, not much you can do right now, but wait till you'll get the scan and faults identified. Keep us posted on what they tell you.
With good battery, the whole car shouldn't lose power even if it doesn't start. So, there must be some electrical gremlin. Let's see what they say.

[beezie84]

So the dealer just basically cleared the codes and had no other suggestions or root cause for my issue. There was multiple codes for parking brake. I drove the car a couple days and she just died again in my parking spot. I opened the door and got out to look at something left the car running and got back in and had the parking brake malfunction and couldn't restart the car, I disconnected the battery and reconnected and it went completely dead same as before. Before it went completely dead I scanned it with my code reader and got all the same parking brake codes. I just ordered a obdeleven pro from amazon should get here by Wednesday and a used parking brake module. Question I have is it possible to do a reset on the car without vdcs will obdeleven be able to? I really don't want to have to tow it back to the dealer.

[audrobotic]

Since you're not in the driest climate, I would venture to say your root cause may be related to corrosion somewhere and/or water getting into the car. One quick thing you could check would be the trunk inside panels.

[beezie84]

I checked the trunk panels and battery area. All dry and looks clean as new no signs of moisture. Only thing I haven't checked yet is the connectors to the actual parking brake. I've read quite a few threads about people having issues with the parking brake module but none of them seem to have a dead car issue like me 😕

[shiz222]

Why not take it back to the dealership since they didn't actually fix the issue you took it there for... We're sure the alternator is actually charging and the battery is actually holding a charge?

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[beezie84]

The dealership was a complete waste of time impossible to even talk to the tech who did the work and it's about an hour from home (it was the closest one to two it to when the car died the first time)
Brand new battery was just put in. I'm hoping I can get some more answers once i get my obdeleven.

[Smac770]

I believe the EPB module is just an unplug old one / plug in new one done deal. You might need to run a basic setting, but see if you have DTCs pointing to such first. There's no coding for the J540.

[beezie84]

I got an OBDelven scanner and i'm pretty sure I narrowed it down to the parking brake module causing a short on the right hand side circuit. I was able to clear the codes and get the car started last night and release the parking brakes from the app (only worked if I did them one at a time, if I released them together either from the switch or the app it would kill the car). I was able to disable all the automatic parking brake functions from the app and everything was running fine until I tried the parking brake switch again, now it's completely dead again can't even get accessory power and the OBD11 doesn't work as well unless I have at least accessory power. Sometimes power will return on its own I can't figure out the trick doesn't matter if I disconnect the battery and leave it off for 1min or 8hours the car resetting itself happens when it wants to. Anyways I've ordered a used parking brake module that should be in tomorrow. Fingers crossed things will just work once I plug her in. I will update tomorrow.

[Smac770]

If you unplug the EPB module, then it's no longer involved in the vehicle electrical system. If there's an issue remaining at that point, it's not with the EPB or the downstream circuits to the motors.

So if the 30-pin is hanging unconnected and things are not working well in the car (minus the EPB being non-operational), then you have something more going on.

It also makes zero sense for the EPB to be interfering with the vehicle electronics at that level. The power to the EPB for the motors is on direct lines from fuses.

I'd probably start by making sure all the pins in that 30-pin plug look ok and are not shorting together. Then make sure the vehicle is working fine without plugging any EPB module in at all. There's no need for it critically unless it's a manual.

[beezie84]

Well the new (used) parking brake module didn't work same issue. Now I'm stumped no idea where to go from here. When I was able to get the car started I tried disconnecting the module but I didn't risk driving around with it disconnected. When I plugged in the new (used) module same thing happened car died when I used the parking brake button.

The only codes im getting with the obd11 is for the parking brake module and central comfort module.

[beezie84]

*central convenience module

When I can get the car started I'm able to reset that code but the one that always seem to trip everything out is the parking brake module

[beezie84]

Also when the car is dead the only electronics I get is the flashing parking brake light if I pull up on the switch or open the door I can hear the relays clicking and the light flashing but that's it

[beezie84]

Checking the voltage on the 30pin plug pin 13 is only showing 2v and pin 15 is showing 12v. I believe pin 13 is the right side (which is what keeps throwing the code short to ground) checking the fuse block for the 2 30amp fuses one block shows 12.3v and the other 11v. Anyone have a wiring diagram?

[beezie84]

Where does the 12v feed to fuse block "b" in the trunk come from? I'm only getting 2v on the entire block, this would explain why I'm getting no accessory power to the car at all because that's where all the fuses for the vehicle electrical systems are.

[Smac770]

The wiring diagrams as well as the workshop manuals are always available at erwin.audiusa.com, pay for a day, get all the PDFs for your VIN.

You can bring up an outdated copy in a pita ui on cardiagn.com, better than having nothing.

"The only codes im getting with the obd11 is for the parking brake module and central comfort module. " The those codes are? Find the history log so you can copy/paste the complete actual error text to the thread.

Pin 22 is 12v for the J540 electronics. Pins 13 and 15 are 12v for the motors. Pins 28 and 30 are both ground, that tie together in the harness, on the way to the chassis ground point.

So with the 30-pin unplugged, you measure 12v from pin 15 to pin 28 or 30? And 12v from pin 22 to pin 28 or 30? But only 2v from pin 13 to pin 28 or 30?

Do you measure the same if you check the voltage at the fuses themselves? Fuse 7 in column "B" goes to pin 13. Fuse 7 in column "C" goes to pin 15. It's not fuse block B, it's called fuse panel F. With columns 1 through 5, or "A" through "E", front to rear, since that's actually imprinted on the plastic.

It sounds like the voltage at fuse "B7" as we'll call it is already poor, and gets worse en route to the J540. All the fuse positions in column B are hardwired together to a common supply. Are you seeing the same sub 12v voltage on all the fuses? Even still, if it's 11.x v at the fuse and 2.x v at the plug, there's more issue than the supply to fuse column B.

Audi B8.5 power distribution.jpg

[beezie84]

thank you for your reply!

This morning I'm only getting 1.7V at fuse column B (this is the column that has the fuses for right side parking brake and the CCM). So yes the common supply is only reading 1.7V. The only electronics I get in the car now are: flashing parking brake light when I activate the switch and I can hear the relay in the EPM clicking, I get the hazards but only the front lights and mirrors, and the puddle lights on the doors.

I'm using OBD11 so I cant copy and past the codes here but the main two are:

C101314 Control Module right channel voltage supply - open circuit/short to ground
C100E13 Right parking brake motor voltage suppply - open circuit
01330 Comfort system central control module - no signal/communication
00384 Optical Data bus
00456 Access/Start authorization control module - no signal/communication
01334 Right rear door ctrl.module - no signal/communication

Sounds like something is shorting to ground somewhere but I'm kinda lost now. This all started with the parking brake. First it was just "parking brake failure" warning that would flash and go away, then it escalated to occasionally flashing and shutting off the car, then escalated to killing the car completely. When it would magically regain power activating the parking brake switch would kill it instantly. I swapped the EPM but obviously theres an issue elsewhere because now I'm only getting 1VDC to fuse panel to supplies the right side parking brake.

Any ideas??? I'm supper frustrated I spent 25k on this car not even two months ago and it's been sitting dead for almost 2 weeks now :(

[audrobotic]

https://www.audizine.com/forum/showt...oad-water-leak

something like this maybe?

[beezie84]

Mine is all dry back there.

[Smac770]

You see in my diagram how fuse column B and some fuses in column E are direct wired from the battery, output post C. So if output post C is reading 12v to battery negative, but the fuses in B are reading very low, there would seem to be a failure of the splicing in the wire path, or failure of the connection of the wire to the fuse holder. The related fuses in column E, 1/4/5/6. If installed, are they reading 12v or 2v?

And issues with corrosion on the splicing of these wires from battery post C to fuse panel F has been seen here before.

[beezie84]

Outpost C is reading 12v to batt neg. Column B are all reading 2vDC and the 7.5amp fuse on column E is 2vDC the rest on E are 12v. The connection to column B is good and it is reading 2v at that point as well. Before tearing that wire out and tracing it back to the battery C terminal I'm going to pull all the fuses from column B and see if any of those were drawing the current down to ground (so far i've only focused on the parking brake motor fuse). It's making it hard to believe that it is a bad wire splice or corrosion, like i've mentioned before everything looks like factory original no moisture anywhere and it looks like I'm the first person to be looking into any of these panel. When I went in to change the original battery I don't think anyone had even been in the spare tire well before.

[beezie84]

OK - - so if I pull all the fuses from column B and the one 7.5a fuse from E I get 12v on the whole column and 12v on the slot in E. But only if all the fuses are out if I put any of of them back in it goes back to 2-3v!

[Smac770]

"one fuse from E", specific position numbers is more informative. So fuses 1, 4, 5, 6, which are actually installed in the car? Which one did you remove?

Looking more and more like corroded splice. Voltage drop across any distance is V=IR. R being resistance and I being current flow. If there's no current flow, there's no voltage drop, so you'll measure 12v the whole way. As soon as you have current flow of any amount, it multiplies times the resistance, and that voltage is lost across that distance. Now your 12v at one end becomes less than that at the other end. But for it to drop that much, that resistance must be substantial.

What I would do is disconnect the battery negative so there's no complete circuit back to the battery. Then measure the resistance from "post C" to a fuse slot in B and from "post C" to a fuse slot in C. You'll probably see the resistance value be very low to C but much higher to B. You're going to need to get under the cargo hold trim and follow the wire from post C to the right rear and see if you can find the splice point to inspect it.

[beezie84]

Thanks so much for your help man! Found the problem today where the 12v wire was spliced it was corroded and hanging on by a strand.

Hopefully this is the last electrical issue I'll have.

[Theiceman]

Thanks so much for your help man! Found the problem today where the 12v wire was spliced it was corroded and hanging on by a strand.

Hopefully this is the last electrical issue I'll have.

why was a 12v wire spliced ?

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[audrobotic]

Thanks so much for your help man! Found the problem today where the 12v wire was spliced it was corroded and hanging on by a strand.

Hopefully this is the last electrical issue I'll have.

Awesome! Got any pics?

[Smac770]

That's the stock configuration. Note the diagram I linked. The lead from the battery output post C goes to several outputs. There's lots of splicing on the 12v distribution lines, as well as every CAN and LIN comms line, etc.

Finally found the thread of similar issue where the guy had posted the splice corrosion in the same place: https://www.audizine.com/forum/showt...1#post14871937

[beezie84]

Trying to upload some pics! Still scratching my head to how that corrosion started. I'm probably going to run a new wire from the battery instead of trying to cut it back and re splice.








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[WHT13AR]

Where exactly in the vehicle is this??

[Smac770]

It's in the right rear, under the fuse/relay panel. There's the main wire from the battery positive, but then it has to splice into feed wires to the fuse column B and several individual fuses in column E. Then there's a second wire from the same battery output post for column C and some other fuses in column E. Per my diagram I posted.

So that's two vehicles with identical corrosion on that same splice. It wouldn't be the first time Audi had a string of corroded splices in a particular spot on the B8. The corrosion of the G395 LIN line, and instances of corrosion on the splicing of the wheel well harness. The other vehicle in the link I posted was also a 2015.

[beezie84]

Would you recommend opening up all the of the wire tape and inspecting the other 12v line? Or just don't touch it and leave it be?

[rockstar143]

I will admit I didn't read ALL the responses but stupid question...have you replaced that 7 to 8 year old battery yet?
New cars do NOT do well with dying cells in the battery...they work intermittently and wreak havoc on the odd individual
electronic control modules...

[beezie84]

I will admit I didn't read ALL the responses but stupid question...have you replaced that 7 to 8 year old battery yet?
New cars do NOT do well with dying cells in the battery...they work intermittently and wreak havoc on the odd individual
electronic control modules...

Yes the battery was the first thing replaced once I started having the issues.

[Smac770]

Would you recommend opening up all the of the wire tape and inspecting the other 12v line? Or just don't touch it and leave it be?

If you don't have unexpected voltage drop measured, then you don't have an issue to find, imo.

[beezie84]

If you don't have unexpected voltage drop measured, then you don't have an issue to find, imo.

Spoke to soon lol after splicing together the bad wire and trying to start the car found myself in the same position no power! 2v on the fuse panel beside the one that was just having issues. While rustling around with the wires found a second bad splice on the other 12v lead from the battery terminal if I poke at it power comes back, haven't opened it up yet but I can see the green corrosion coming through the factory wire wrap. Pain in the ass spot as well. It's right under what looks like a vent (its right where the tail light is) I'll get some pics tomorrow when I tackle that repair.

[eljay]

Oh man, what an ordeal!
Thank you so much for posting back, BTW! Please continue to do so and I hope this gets you on the way!

[beezie84]

Here's what's hopefully my last pictures. This looks like its the exact same spot as the previous post about the 2015 S4. 2 10gauge wires spliced together with 2 14gauge wires. I used terminal blocks to put everything back together and wrapped it all with rubber electrical tape. I'm not sure yet if I'm going to go back in and solder everything but the car is back up and running again! Now just a minor exhaust leak to tackle and she'll be like new.

@Smac770 Thanks again for all the help!!!!


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