AudiFailed

I've been waiting for my car to be repaired Since February 3, 2023, almost 8 weeks now. Audi USA tries to lay blame on the dealership stating the dealership is experiencing a parts problem. It will take a miracle for me to purchase another Audi

ThomasWShea

If someone is willing, call your dealer, and say you want the old alternator back. It think it'd be interesting to yank the electronics, and see what there is to see on the board. Inspect for blown components etc.

retom

I am convinced that any average electronics technician is able to repair it, provided that he finds the right new electronic components. Transistors are said to burn out. This is how it looks inside:

stonehill

If mine dies I’ll do that and dissect it. I hope it doesn’t . As an EE I am capable and have all the tools. Only roadblock is the orange epoxy conformal coating on it. Would be a stinky job. Maybe the guy from Chicago can request his, I’m close enough.

ThomasWShea

there is no way to dissolve that coating w/o harming the board or other components?

stonehill

Not really, a heat gun or soldering iron and a small screw driver will chip it away. Replacing the power transistors would be easy. The small wave soldered items would take a bit of time. I don’t know why they say they are not repairable. A standard alternator has the same voltage regulator on a circuit board on the back. When you buy a remanufactured one the regulator gets replaced.

stonehill

As I stated they are asking a lot out of a small device. If they say it’s not repairable it probably is smoking the windings (coils) in the alternator. 90% of the time in a standard alternator it’s either the electronics or the bearings that go. This brings up a glaring problem with EV’s in general, the motors are physically small for the supposedly high horsepower they produce, they play games with the continuous duty ratings and the belt pulley ratio. It is probably a hope that they are never used at full capacity a lot in a short period of time like typical congested highway traffic. I did read prior to buying one that a complaint was hesitation and no power on restart during entry into a lane from a stop sign or reaccelerating from a coast. Being my 3rd audi with the stop start feature i figured to shut it off every time. Which someone would have a hack for it.

ThomasWShea

Sounds like your knowledge extends past ours on the electronics side. The way the BSG is being used on the Q8 platform is somewhat TBD. We would like to know for sure which cases the Q8 platform uses. Right now, there is nothing from audi that says it is used to boost the engine, or for coasting highway speed stop start on the Q8 platform. @retom , @Mrclopec and I believe the BSG in the Q8 platform is limited to advanced stop start only - which would be engine off at low speed around 13 mph while coming to a stop, then back on. Some Q8 cars (SQ8 cars in the US in particular) don't even have the BSG w advanced stop start, and are using 12v stop start via traditional starter. Excuse the crud and probably oversimplified summary: Is your theory that on start, at higher speeds the BSG is killing itself?

angrypengu

This is not correct. The BSG does absolutely apply up to 60nm of torque (see pg 30/84 here https://static.nhtsa.gov/odi/tsbs/20...49155-9999.pdf) - I believe up to a total of 5 seconds at a time but IIRC. I'm too lazy to find the actual SSP for the EA839, but it's the same engine. It's easily verifiable. The BSG does add quite a bit of torque when just driving around town or when flooring it.

In NA, it's used as a SS system, and to supplement torque from the ICE. None of the coasting functions that we see in EMEA are found in AMER.

angrypengu

This theory has little legs to stand on considering we see 0 problems with a similar setup on Mercedes vehicles (ISG is their term, or integrated starter generator). They're both P0 MHEVs.