I am going to attempt an egt gauge install this weekend. I have read the Hoot method for tapping the exhaust and the guide to gauge hotness. But I can't find the which wires or fuses to tap for my LLY.

Which fuse or wires to tap for
Instrument lighting (so the gauge will be controlled by the instrument panel dimmer)

A picture would be great.

Thanks,

I do not know what gages you have, but I have the autometer ultralites. I just wire the lights to be on whenever the key is on. They are not bright at all, and in the daytime you can not even tell they are on at all. I dont know if wiring them into the dimmer will make a big difference. Light them up real quick they are probally not that bright.

Here you go. It's an excellent guide. Just follow BMDMAX's link.
http://dieselplace.com/forum/showthread.php?t=21492

I tapped the dimmer and it works great. Pull the dash apart and pull the dimmer box out. I think it is the brown white(maybe violet white) wire, but you can use a test light to figure it out. The 05's don't have any fuse panel taps with dimmer function. I think some older model duramaxes had the fuse tap option. Do a search on dimmer tap, gauges, gauge light source, or dimmer...it might tell you the correct color wire to tap. I always forget.

Thanks everyone. I got the EGT gauge installed. I took SSNIGHTMARE's advice and just just wired the gauge light on with ignition on. I had a hell of time with the tap though. I have an old Craftsman Tap and Die set. The 1/8" pipe tap had never been used and I could not get it to bite. I had another 1/8" pipe tap that came as part of two piece set when I did the EGT on a Ford. It had never been used either but it did the trick.

The Hoot method did work quite well, but with outside temps about 90, the tap and my hand were getting quite hot, nothing a glove didn't cure though. Thanks Hoot.

I did find a handy fuse tap at AutoZone. It plugs into a mini fuse and has two fuse slots and a lead wire. One slot is the original circuit and the other is for an accessory, in this case the gauge power and light.

The Autometer gauge said to fuse with a 1 amp fuse. Smallest I could find at two auto parts stores was 2 amps. I'll keep looking...

Thanks again all, this forum is way cool...

Just take your light switch out of the dash. You will see where the harness connects to it. Strip a small section of your wire. Be sure that the graound is already connected. Touch it to the base of where the wires are, you could see a metal contact there, and operate the dimmer. If it is during the daytime, turn your lights on. This way the dimmer switch works. Mine turned out to be a violet/white wire on my 04.5 lly.Once you find it, you can tap into it. Mine works during the day with the ignition on, but I do have control in the evenings as it works with my dimmer switch.

Just take your light switch out of the dash. You will see where the harness connects to it. Strip a small section of your wire. Be sure that the graound is already connected. Touch it to the base of where the wires are, you could see a metal contact there, and operate the dimmer. If it is during the daytime, turn your lights on. This way the dimmer switch works. Mine turned out to be a violet/white wire on my 04.5 lly.Once you find it, you can tap into it. Mine works during the day with the ignition on, but I do have control in the evenings as it works with my dimmer switch.

:exactly: Same here - Its nice to have the ability to dim at night vs. full brightness. Just my opinion though! Glad to hear you got it done. Pretty intimidating, but not as hard as it appears to be, eh?

nope not at all

where is everybody running wires thru the fire wall?

where is everybody running wires thru the fire wall?

I believe that in the "Guide to Guage Hotness" (link below), there is a location highlighted to drill a small hole. It is right on the firewall just a bit off center to the driver side and to the right of the master cylinder. There is already a hole on both sides of the firewall in the insulation so its pretty easy to find.

Here is the guide link: http://dieselplace.com/forum/showthread.php?t=21492

There is a nice flat spot just off-center driver's side on the firewall. There should be a hole or spot with no insulation there. It'll be above the accelerator pedal on the inside.

:exactly: You were a bit faster, but we were consistant with our info!

:exactly: You were a bit faster, but we were consistant with our info!

Which is pretty rare for me since my typing sklls are about equal to a chicken :eek: .