Ground points - schemas needed

Hello dear community.

I'm having some hardly troubleshootbale problems with my Golf Mk6's alternator/battery. The voltage at the battery is only 13.0-13.2 Volts with car idle.

I've visited the alternator shop and the techs were scratching their heads. They suggested trying to clean ann the ground points firstly. I have an appointment for the next week.

Now the question. Does anyone have any schemas or diagrams showing all the ground points for any Mk5 or Mk6 platform car? I just want to be sure we find and clean them all.

Any input appreciated.

Thanks in advance.

A very important ground on an A5 that can work loose over time is underneath the air cleaner box. It is the main chassis ground and can cause a multitude of problems if it is loose.

Not sure if the A6 has the main chassis ground in the same place, but I would imagine it does.

Ol'Rattler,
thanks for the reply.

Do you mean this ground seen in the pic between the two green arrows?

Where does the other end go? Engine or transmission? Any hints for finding the other end?

What is the voltage at other times- are you aware if there is any "smart" charging functionality on this vehicle?

I have a few questions:

1. What's the production date?
2. Are there any fault indicators/codes?
3. Does the gen. lamp (battery symbol) illuminate when the ignition is switched on?

DPM said:

What is the voltage at other times- are you aware if there is any "smart" charging functionality on this vehicle?

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Voltage almost never exceeds 13.6 Volts at the battery. It's really rare to see that voltage there. I know. And this one looks like "dumb battery discharge feature". It's not charging enough, seriously.

jcrews said:

I have a few questions:

1. What's the production date?
2. Are there any fault indicators/codes?
3. Does the gen. lamp (battery symbol) illuminate when the ignition is switched on?

Click to expand...

1. Build date is roughly 27th week, 2010
2. "Drive battery" fault code in 09 Centr. Electr. and G83 sensor multiple fauls (not sure if this is related)
3. Yes. And it doesn't go off quite for a while. I haven't payed attention but I think on my previous Mk5 the light went off sooner. On this car, after starting the engine, the red light is on for 1-1.5 seconds.

Henrick said:

Ol'Rattler,
thanks for the reply.

Do you mean this ground seen in the pic between the two green arrows?

Where does the other end go? Engine or transmission? Any hints for finding the other end?

Click to expand...

Ya, I think that's the one although I think the A5 also has the chassis electrical ground there, as well. I cant remember for sure.

It looks like the other end goes to the tranny just forward of the shift mechanism. Also, one or both of the red wires just forward of the green arrow on the drivers side might be chassis grounds, as well.

Thanks!

I forgot to ask, what engine code do you have in there?

Engine code is "CAYC"

Looks like the problem was weak ground. The tech routed additional earth cable: one end bolted to the engine, another straightly to the battery negative terminal. We have also cleaned the connectors under the air filter box and near the starter on the tranny. As a result, 14.2 Volts at the battery, 13.80 Volts with low beam, front and rear fog light and high beam on.

I'll keep an eye on this issue just to be sure this isn't an intermittent effect.

I had some trouble with my terminal machine, but here's the answer to your original question:

Golf VI Ground Points

jcrews, thank you so much!
I'll need to po the hood and continue the cleaning. Looks like there are way more ground points than I expected.

You guys have a similar diagram for the A5 BRM? I'm having many codes with this car.

Good idea to replace negative cable. At least check all connections of cable. It grounds to chassis and motor. Easy to follow cable and check both connections

Loose and corroded grounds can really raise havoc with a modern car. On my A5, The ground under the air cleaner has worked loose twice since I've owned it. The second time, I got a metal (not nylon) lock nut for it.

A guy posted several month back that his electric assist steering was acting up. The stealer recommended replacing the rack for something like $2500.

Had him check the ground under the air cleaner and it was loose. Cleaned and tightened it and his steering issues were gone.

The diagram shared by jcrews worked perfect on my mk5 BRM

Ol'Rattler said:

Snip... Loose and corroded grounds can really raise havoc with a modern car.

Click to expand...

Not only a 'modern' car, but also on older BMW's such as the 1983-1988 E28 model, which we owned for 30+ years and dealt with many ground and connection problems on it and others. We've used this http://store.caig.com/ product for many years on many vehicles with excellent results. Very effective on fuse terminals, too, especially the older ceramic type held in place between two spring contacts.

jcrews said:

I had some trouble with my terminal machine, but here's the answer to your original question:

Golf VI Ground Points

Click to expand...

Do you have a link for the Jetta MK5 Ground Points?