D3. Some strange electrical issues

[ytt105]

My 2005 TDV6 has started doing some funny things. The stereo, (aftermarket Android 2 din GPS system) will sometimes not operate at all, (no power). It will start when I put on the driving lights, then operate as per normal.

Also, my central locking is getting a bit more iffy.

One of my brake light globes was blown, but no change when it was replaced.

Brake light switch would probably be about 4 years old.

Alternator is less than 1 year old.

It certainly sounds like its an earth problem.

But which one?

[Jpkat]

I'd try making a new earth from the battery to chassis first, if you don't want to make a complete earth wire then try a jumper lead from negative to a nut or bolt on the chassis, if that doesn't work then you have a gremlin and it's going to be fun to locate, but it can be done.

[drivesafe]

It does sound like a earth problem and the D3 has a known problem with the connection on the cable running from the block to the chassis, where it bolts to the chassis in behind the plastic wheel arch.

This connection at the chassis bolt corrodes but you can’t see it.

Try the jumper lead test as above, but go from the cranking battery’s negative ( - ) terminal to an earth point on the engine block.

You can do a similar test with a multi meter, just measure between different points, like above, and make sure there is no reading above something like 0.01v

[ytt105]

Drivesafe, where are these earth connections?

I understand I need to take the passenger side, inner guard cover off, but where is the one on the block?

Thanks
Trev