Mystery Lights and No Go

I have a 2007 VW GTI that whose clutch just went out (pushed to the floor, would not engage gears). The car was towed to a VW dealer who replaced master cylinder. When it still was not working correctly, they diagnosed and changed a leaking slave value. The said they would have to “drop the transmission” for this. When the dealer called to say the car was ready they mentioned they had to replace the battery. Strange because the car’s battery was 2 months old with a 6-year warranty. After 20 minutes of driving the battery light flashed on and off. Another 20 minutes later the battery light was out but air conditioner fan stopped working - then started up again. Next the power steering light came on, followed by the air bag warning light, and then all the lights. Meanwhile the car was losing power. I limped to a parking lot and stalled. It would not start again (grinder) but then .5 hour later it did. No risking it knocking out again in traffic, I had it towed back to the dealer who two days later cannot find the problem. Help, please!

The good thing about all this is that you’ve got a manual transmission. That will simplify things. Assuming that your car is like most manuals, there isn’t any electrical component to the clutch’s operation. Needing to replace the clutch MC and slave in a 2007 isn’t an unusual thing. I had to replace the clutch master cyl in my Corolla a couple weeks ago in fact.

Here’s what I think happened. Whenever I work on my Corolla I always disconnect the battery negative first. Prevents unintended shorting circuits out during the wrenching. If the battery remains connected, it is easy to create an unintended current path through the wrench, which can do damage to the car’s circuitry, as well as damaging the mechanic sometimes. That’s why I disconnect the battery. I speculate – and it is just a guess – in your case they didn’t disconnect the battery, and during the wrenching to fix the slave cylinder they shorted something out, which damages the battery and possibly some other circuitry.

It’s also possible that the battery problem is unrelated, nothing got shorted out, and that they disconnected something in the process of fixing the clutch, and forgot to reconnect it, or connected it to the wrong connector somehow. Or forgot to re-connect a ground.

Does the dealer acknowledge that there is a problem? I.e. has the dealer shop been able to duplicate it?

Have the car towed to a reputable independently owned and operated shop.
Clearly the dealer is either incapable or unwilling to fix it properly. Stop wasting your money there.

@ GeorgeSanJose. I appreciate that you shared your experience with your Corolla. I think it is probable that something similar is the case with the GTI. The dealership acknowledges there is a problem but they don’t know what it is. They have had the car in the shop for two days and had said it will be noon on Monday before the report back again. After spending $2000 on the clutch and slave, I am fearful they are going to come back with something that is on me (i.e., the alternator). There has never been a problem with the electric so I hope you are correct that this is their mistake and that the own up to it… What you have shared gives me a bit of something to go back to them if they don’t.

I would suspect the electrical problems you saw are due to a faulty alternator. It may be intermittent or a constant problem.

I’d quiz them as to why they installed a new battery. That’s a bright red burning flag.