dash lights dont turn on when headlights are on

[alexrhoads]

Hey i have a 72 911 and just recently i was driving at night and i wondered how fast i was going and then it struck me i could not see how fast i was going...this is kinda a problem.. anyone know what it could be?? if i pull the lever to turn the lights on out slowly the dash lights turn on for a second but when they are on the head lights are not. im just stumped

[Joe Bob]

Stupid question but did you try twisting the knob? If you did and still no dash lights, it's likely the switch rheostat is bad.

[alexrhoads]

yea i twisted it and nothing changed and sorry i'm new to cars myself so i'm learning as much as i can! i'm just a 17 year old haha

[jimtweet]

i had some weird lighting issues man, some times lights would work sometimes not, replaced light switch and all problems went away, i know that isnt what you want to hear, but always a good place to start

[Winter]

Before you replace the switch, ensure that all the connections of the wires to the switch are clean and nice and tight.

If there is a willing Pelican near you, it may also be possible to try a good known switch to trouble shoot the problem prior to spending money on a part you may or may not need.

Good luck!

[86 911 Targa]

Originally Posted by Winter

Before you replace the switch, ensure that all the connections of the wires to the switch are clean and nice and tight.

If there is a willing Pelican near you, it may also be possible to try a good known switch to trouble shoot the problem prior to spending money on a part you may or may not need.

Good luck!

Connections: I agree, as the (wire) connections from the dash lights, to the light switch, are in close proximity to your climate control sliding switches which can dislodge the wires.

It's time for the contortionist-under the dash look-see.

Also, if you do replace the switch, fuse the CKT with a 3A fuse.

The CKT is for our '86.

You can also try this.

http://www.cannell.co.uk/911_72-89_Workshop_Manuals/Porsche%20911%20Workshop%20Manual.pdf

Good luck,

Gerry

[Revvin 911S]

The headlight switch is the likely problem. I was having a similar problem of no dash lights when headlights on, as well as one of the headlights randomly going off then back on and the radio turning off and then back on when the headlights were turned off or on. The wiring for pretty much all of the dash electronics is through the headlight switch so a switch going bad can have all kinds of electrical symptoms. I replaced my switch and everything works as it should. Double check connections on the switch first though, as it may be a loose connection. When you install the new switch it is easy for some of the wires to get bumped loose when you are fitting the switch back into place under the dash.

[kidrock]

Before you invest in a new (or good used) switch, go to Radio Shack and pick up a can of electrical contact spray cleaner. Hose your switch down really well with this stuff while turning the knob back and forth, then report to us back here.

[alexrhoads]

thanks guys i just cleaned it all up and it works like a charm now!! Now if only fixing oil leaks was just as easy!

[kidrock]

Alex, glad to hear it was cheap and easy, like a whore's ass on Nickle Night.

Be advised, you will find a good number of Porsche electrical symptoms will be similar to this. Try cleaning stuff up first before tearing into things and needlessly throwing away $$$$.

[DRACO A5OG]

17, Damn, starting early eh?

Enjoy little Brother!

So where does she leak? Wash the engine and underside and take fresh pics, we can probably help, post a thread.