greg51

Hope everyone had a good Christmas.

I replaced the radio on my 99 Civic DX and my daughter called and said the dash lights do not work. I replaced 2 fuses due to my error when cutting old radio wires without the battery unhooked. That was dumb but anyway, with fuses replaced, the dash lights still do not work. So I gave her a flashlight until she could bring the car back for a few days.

Last month I wired the new aftermarket radio per the supplied diagram, except I had 2 car wires to decided what to do with. They were a red and red/black wire that my manual shows as being interior lights.
The aftermarket radio also had a wire labelled "Illumination". So I twisted the red & red/black wire together and soldered to the "Illumination" wire of radio. Likely another bad electrical move.

Today I have cut the red/black wire from the red/black & Illumination wire connection. Taped the wire end. Checked all the fuses were good.
With key in On position and headlight switch on, dash lights in instrument cluster do not work.

Car has auto trans and gear position light works when lights are off. Gear position light does not work when lights are on.

Based on another post, I may interrogate(meter) the dimmer switch tomorrow. All your expert help appreciated.
Thanks
Greg

grumblemarc

iTrader: (4)

Really can't say what you did since you hacked the stock harness instead of using the proper aftermarket wiring harness. Even then I don't know why you would bother with any interior lighting (black/red) wiring when all you were doing was installing a new deck. If you have anything from the new deck wired to the dimmer switch remove it immediately. The only power wires you should have bothered with were for constant power (red), switched power (yellow) and a ground. all others would be speaker wires and anything else you leave uninstalled.

Check the underhood fuse. Can't remember which one it is offhand.

Nobody123

Not relevant to the question.

Wrona

or you can grab a paperclip and put it into the connector between the two wires and done

98civdx

Check the 7.5amp fuse for the interior lights, its in the under hood fuse box.

Nobody123

I'm sorry I said anything. Heed all advice at your own risk.

kyden

there are two illumination wires, you probably tapped the wrong one. (if i recall correctly, the colors don't match up on aftermarket harnesses)

greg51

Cut both red and red/black wire from radio and shrunk shink tube over ends to insulate. Only wires that are connected to radio is battery 12v, key 12v, ground and speakers. Checked all fuses are good underdash and under hood. Dome light has always worked before and after radio install. No dash lights.
Other suggestions?

Wrona

funny how i have had a paperclip in mine for 2 years and 3 other 96-98 civics even my friends have same thing what do you think the jumper is a piece of metal with 2 plugs exactly thesame as what i said except mine isnt a fancy green connector

98civdx

Are you checking with a multi meeter, or just looking at them?


Check the back up fuse under the hood aswell.

Nobody123

I don't want to thread-jack. PM if you would like to discuss.

greg51

Just visual check of fuse. The blow very visible but understand you point.

Went to car and put in reverse with key on, backup lights work.

Nobody123

I am sorry, greg51. I misread your original question complete.

Short version: in the harness going to the radio, remove the red wire and insulate. You can leave the red/black wire connected to the radio illumination wire. If that still doesn't work then check the 7.5A fuse #30 in the underdash fusebox.


Long version: the dash lights brightness is controlled by the dash lights brightness controller. Power goes to the light bulbs (gauge lights, A/T gear position indicator if auto, hazard switch, rear window switch, heater control, cruise control on/off switch, and radio).

Current then goes to the dash lights brightnes controller instead of directly to ground. The controller controls resistance to ground based on the brightness selector **** to increase brightness (less resistance) or to dim (increase resistance).

When you hook red and red/black together without a load (a light bulb), it will create a short and backfeed current to all the bulbs I said above. Then you won't have any light because current is not passing through the bulbs and then to ground.


Synopsis: very few aftermarket radio will allow you to control the radio display brightness with the stock brightness controller. It's usually just a lights-on signal. If you read the manual for your radio, it will specifically say to not connect the illumination wire to the dash lights controller wiring.

Most aftermarket radio has an internal setting to adjust the display brightness independent of the dash brightness controller setting.


If you let me know the make and model of the radio you're using I can check for you as well.

Good luck.

greg51

Thank you for the explaination. I missed the part in instructions about not connecting the illumination wire. The radio brightness is of no concern, just the dash lights so the gas gage and speedo can be seen. Don't need anymore certificates of performance.

I will recheck the fuses with a meter especially #'s 28, 30, & 48 which relate to dash and radio for a '99 civic.

The brightnes controller must be damaged from the crossed wires or just failed by chance. Thought I would pull the brightnes controller and meter the wires, w/ key ON. Temporary jump the brightnes controller and see if lights work and go from there.

Wrona

lol and the point would be

Nobody123

Just do what you want. The guy's problem has nothing to do with the dome light bypass.

Nobody123

If you want to check the dash brightness controller, do this. Unplug the controller.

In the connector going to the controller, temporarily jump the red wire directly to ground. Then turn on the combo light switch to activate the parking lights.

If the dash lights work, then your controller is busted. If not, then you have a problem further upstream.


By doing this test, you're bypassing the controller completely and just grounding all the lights directly to ground, and allowing them to be at their brightest setting.

greg51

Well it appears the brightness controller is faulty. Measured 12v on red wire to grd and red/black wire to grd. Black wire has continuity to grd. Jumered red wire to black and dash lights lit. Hazzaa!

Removed switch to measure resistance across brightness controller. I'll use the wire color reference instead of connector positions 1, 2, & 3. No continuity or resistance measured accross any terminals, except red and black. This measured a constant 7 ohms regardless of thumb wheel position. Would expect to see some resistance change.

Appears the controller is a dealer item, so I'll check my local pull-n-pay and see what turns up. May result to an insulated jumper wire between red and black wires.

Thanks for the valuable input from those that offered intelligent discovery.

grumblemarc

iTrader: (4)

Nobody123

You got it right the first time. He just didn't know what colour the dimmer switch wire is.

JJT211

Thanks Greg!

Had SAME exact prob. I just spliced red & black and bypassed the whole dimmer switch....I got lights and im happy

JDMboi27

I know this post is super old but where do I connect the paper clip I have 93 Honda civic I'm only seeing yellow and red with Silver and on the other side green and red and blue & silver (passages side)

Former User

Red to Black in dimmer switch connector. Make your own thread if you have additional questions.