Hello everyone.

Im currently in the process of installing additional gauges in a 300TDI (Voltmeter; Oil Pressure; Boost). Apologies about the rudimentary nature of some of these questions, but electics is not a strong point of mine!

1: Instrument lighting
Can I take multiple feeds from 1 of the existing instrument lighting wires? (e.g. the cigarette lighter) or do i have to install a separate wire for each new interment and if so where do they go to?

2: Ignition
Likewise can i take multiple feeds (i.e. 3 separate wires to each of the new instruments but all connected into the existing ignition wire that serves the radio)

3: Earth
I assume its ok to earth all 3 new instruments to the same earth?

4: Positive/live
likewise can the instruments (those that require a live feed) all be tied into a single existing live feed

Again - apologies that this may be very simplistic - i can't for the life of me remember my O Level Physics on electricity!!!

Many thanks in anticipation
Gary

1: Instrument lighting
Can I take multiple feeds from 1 of the existing instrument lighting wires? (e.g. the cigarette lighter) or do i have to install a separate wire for each new interment and if so where do they go to?you could do as long as they dont overload the existing circuit. look at LED bulbs for the gauges as these draw minimal power and should be ok

2: Ignition
Likewise can i take multiple feeds (i.e. 3 separate wires to each of the new instruments but all connected into the existing ignition wire that serves the radio)chances are there will be 2 feeds to your radio, a permanent live and a switched live (that only comes on when the key is turned). Have a look in your fusebox, there may be a spare slot you can use to create a new permanent live feed (if ones needed) that's dedicated to the new gauges... the good part of this is, if the new gauges do blow a fuse or something goes wrong then it shouldnt affect the rest of the car

3: Earth
I assume its ok to earth all 3 new instruments to the same earth?
yep

4: Positive/live
likewise can the instruments (those that require a live feed) all be tied into a single existing live feedsee the note above about a possible new feed from the fusebox

Small comment from me. Please be carfull with the wiring. I made a small mistake installing a car radio, took the wrong feed wire and all most burned the whole wiring harness. Ask somebody to double check it for you if your not 150 % sure.

Smaller but equally important thing from me, If you think you may be wanting to add more electrical extras, think about adding an additional fuse box fed directly from the battery. All new wiring of the correct gauge and no chance of overloading old brittle looms. ( from some one with 3 dashboard fires under his belt)