Aux Gauge illumination after boost gauge wiring

[gunman]

I have a strange thing happening this afternoon after willing up the illumination for my boost gauge. I wired the boost gauge into the wiring for the aux gauges, now when Iput my lights on it all lights up lovely for about 2 mins thn the aux gauges and the boost gauge dim until they aren't iluminated any more. If I turn the lights out foa a min and back on the light up for about 5 secs then dim again and go out.

My volt meter wasn't lighting up either so I replaced the bulb in it today, it is slightly bright than the others if you think this would matter.

Any idea what I have done wrong? Is this not the normal way of wiring up the boost gauge?

Any help most welcome.

[UrS4boy]

Do you know the difference between serial and parallel wiring and the effect on the voltage and current draw?

[gunman]

I think you probably know the answer to that question. I do understand the difference between serial and parallel wiring, and I assume that that is something to do with the problem as you mentioned it. I have wired the gauge in parallel, is this the issue?

[johne]

The illumination for the auxilary gauges is supplied through what Audi call a relay which is fitted behind the gauges. The "relay" is in fact an amplifier to isolate the load of the auxilary gauges illumination from the instrumment panel illumination rehostat which is designed to only cope with the instument panel lights.

As far as I'm aware this amplifier relay can cope with the extra load of a boost gauge but I wonder if the extra load of your boost gauge and a higher wattage than standard bulb in your voltmeter gauge has tipped the relay over it's limit or it's faulty or it's overheating. I'd try removing the bulb from your voltmeter (then you're back to the standard 3 gauge load) and see if the problem goes away. If it doesn't, I'd suspect the relay.

John

[andy10v]

I have a couple of gauges (illumination only), and a shift light wired up from the aux gauges with no issues (wired in parallel).

[gunman]

Chees guys. I was back out to look at it again there and have removed the boost gauge wiring from the aux gauges and wired it from the glove box light instead. Seem to have no issues now although the boost doesnt dim with the intrument panel. Hardly matter as I leave them up full anyway. hadn't go too much time to look at it as I have an MOT at 8.25 in the morning and I seem to have a strange brake issue going on which is another story.

[Knight Rider S4]

Wire the light into the glove box light wiring , live feed when lights go on , easy to do

[gunman]

Wire the light into the glove box light wiring , live feed when lights go on , easy to do

Yep, thats what I did, all seems grand now. I've had the boost gauge in for a year but never wired up the light.

[John B]

Boost Gauge Wiring

Wire the light into the glove box light wiring , live feed when lights go on , easy to do

Yes this is what I did with one of Rusty's superb gauges.....very easy to do.