I cleaned up many electrical faults with my dash system recently, but on fixing instrument lights I find they are on day and night. Any ideas guys on where I connected incorrectly to tie it in with light/ignition wiring?

Thanks in advance any help

Power may be coming (incorrectly) from one of the fuses 6—10, which are always hot. See if pulling them one at a time changes anything.

Power should come (to the rheostat) from fuse 16. Both 15 and 16 get their power from the light switch, and should be dead until the switch goes to the 1st or 2nd position.
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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

Correct me if I'm wrong, but I don't think '79 had 16 fuses...

I know my '76 and '77 don't... I don't think my '80 does either.
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If you listen to the radio in Portland, OR, you may know me as 'Portland's Favorite Soul Brother!'

Bruce is correct. '79 & '80 have 16 fuses. The fuse assignments are the same for both years. If I'm not mistaken those assignments continued through '84.
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'80 DL 2 dr

I've been spending more time in my '76 and '77 lately working on them, and I seemed to remember there being only 12 fuses in the '80.

I double checked, and you guys are right.

See, I don't remember that much because I rarely blow a fuse in the '80... I've been having fuse holder problems in the '77 though (which I will fix this weekend once and for all!)
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If you listen to the radio in Portland, OR, you may know me as 'Portland's Favorite Soul Brother!'

Correct me if I'm wrong, but I don't think '79 had 16 fuses...
My diagrams show 16 fuses for '79 on...

I know my '76 and '77 don't... I don't think my '80 does either.
If your '80 doesn't, you got ripped.


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Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

On most cars the dash lights are connected to the headlamp switch so they come on when you have either the park or headlamps on. The dimmer for the dash lights is connected in series to this connection so when the lights (Park or headlights) are on, you have current to one side of the reostat that controls the brightness of the dash lights and from there to to the lights. I am assuming that you are talking about the instrument lighting circut and not the indicator lights for oil and etc. If you have lights all the time you have it connected to a "hot all the time wire" which is incorrect. A test light goes a long way on finding what is hot and where your feed wire is coming from.
Hope this helps.