Hello, got a couple dash light issues here. first one is, the cluster lights like to dim just a little bit when i have the signal on, or the brake. I think it could just be a ground issue, but i would like to have a second opinion..

second problem. When i get to about 4000rpms in any gear, the lights by the clock all light up at the same time and they shut off once the revs drop down below 4000rpms. What would cause this? im stumped on that!
Thanks for any help and information!

 

Need a little more info from you. Is it an sa/fb, fc, fd?

Ground issue does sound likely, have you also checked the output of the alternator? it might not be producing enough of a charge. I'm sure more people will chime in once you tell us what you're working on, and someone can point you to exactly which ground points need checked, and where they are.

 

The idiot lights all turn on when the alternator places a ground on its White/Black wire. This occurs with the key to on, but the engine not running, and it also does it when the alternator is failing. Sounds like your alternator is failing.

 

Ohh my bad! i have an FC. and ohhh okaaay! that make sense, i guess ill take a gander and see if i can find a new one or a rebuild kit. What are the stock amps of one of these alternators? by any chance is there an upgrade?

 

i would say to check the output of the alternator, cuz my alternator was fine but one of my grounds came loose and would dim the lights every time i stepped on the brake.

 

S4 has 65 amps or so and the S5 is 5 amps more while the FD is close to 100 amps.

 

nice to know

 

Where was the ground that came loose? I have the same problem with my FC.

 

The dash earth is located under the trailing coils. Strange but true, as far as I have found out.

There is a page with all the FC earth locations if you search, can't for the life of me remember where at the moment sorry.