Electrical Help - Interior dims to black after dark
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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St. Jude Donor '12
Electrical Help - Interior dims to black after dark
OK, I thought the problem might be related to the rather abrubpt removal of the stereo. Three fuses were replaced and I still have the proble, so rather than guess and hope I find the problem I thought I'd ask here.
Symptoms:
The "always on" light in the mirror does NOT come on a night like it used to.
When the headlights are on and its dark out the backlighting of the instrument panel goes away.
So what is it ?
Another fuse?
Symptoms:
The "always on" light in the mirror does NOT come on a night like it used to.
When the headlights are on and its dark out the backlighting of the instrument panel goes away.
So what is it ?
Another fuse?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Electrical Help - Interior dims to black after dark (jaa1988)
The map light in the rearview mirror comes on when the ign sw is in run, start , or bulb test along with the vanity mirror light. If your vanity mirror lights will come on, then so should the map light. These lights get power from
the 10 amp gauges fuse. The map light might be burned out or have a bad connection from 12v or the ground wire. When the headlights are on and its dark out, the back light bulbs are dimmed. Shine a flashlight into the photocell at the top left corner of the speedometer and see if the back light gets bright. If it doesn't, then the photocell circuit in the cluster is defective. Check the 3A inst fuse, 10A tail fuse, and the 10A gauges fuse with an ohmeter and observe the fuse clips for bright clean condition.
the 10 amp gauges fuse. The map light might be burned out or have a bad connection from 12v or the ground wire. When the headlights are on and its dark out, the back light bulbs are dimmed. Shine a flashlight into the photocell at the top left corner of the speedometer and see if the back light gets bright. If it doesn't, then the photocell circuit in the cluster is defective. Check the 3A inst fuse, 10A tail fuse, and the 10A gauges fuse with an ohmeter and observe the fuse clips for bright clean condition.
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Re: Electrical Help - Interior dims to black after dark (jfb)
Well, this gives me a place to start.
The funny thing is the map light works when you turn it on.
OK, so I guess I need to figure out how to change the "always on" light bulb.
The funny thing is the map light works when you turn it on.
OK, so I guess I need to figure out how to change the "always on" light bulb.
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Re: Electrical Help - Interior dims to black after dark (jfb)
The map light in the rearview mirror comes on when the ign sw is in run, start , or bulb test along with the vanity mirror light. If your vanity mirror lights will come on, then so should the map light. These lights get power from
the 10 amp gauges fuse. The map light might be burned out or have a bad connection from 12v or the ground wire. When the headlights are on and its dark out, the back light bulbs are dimmed. Shine a flashlight into the photocell at the top left corner of the speedometer and see if the back light gets bright. If it doesn't, then the photocell circuit in the cluster is defective. Check the 3A inst fuse, 10A tail fuse, and the 10A gauges fuse with an ohmeter and observe the fuse clips for bright clean condition.
the 10 amp gauges fuse. The map light might be burned out or have a bad connection from 12v or the ground wire. When the headlights are on and its dark out, the back light bulbs are dimmed. Shine a flashlight into the photocell at the top left corner of the speedometer and see if the back light gets bright. If it doesn't, then the photocell circuit in the cluster is defective. Check the 3A inst fuse, 10A tail fuse, and the 10A gauges fuse with an ohmeter and observe the fuse clips for bright clean condition.
Map light that is controlled by the switch works, Vanity lamps on passenger mirror work.
Tail light and gages fuses are OK
Shine a flashlight on the photocell and the gages light up.
The bulbs that should light up when the lights are on do not light up (shifter, electronic AC backlights, wiper contol). These bulbs have all been replaced.
The radio I installed does not have a dimmer wire so I just capped off the dimmer wire from the wiriing adapter.
I'm guessing the Inst fuse is OK - I replaced it a couple of weeks ago.
So now what?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Electrical Help - Interior dims to black after dark (jfb)
When your headlight sw is rotated fully clockwise with the headlights on and dark out, the dash is very dim and may appear to be out. Try rotating your headlight switch counterclockwise with the headlights on and at night (dark out). This will brighten your dash and I believe that is your dash problem. Your electronic dimming circuit in the cluster may be dimming to fully out when the headlight sw is fully cw, or your variable resistor on the headlight sw is open circuit.
Your always on lamp in the rearview mirror is only on when the headlight switch is in parking light or headlight position and its intensity is controlled by the dimming control on the headlight switch. The switchable maplight in the rearview mirror is a separate lamp and is not on the dimmer circuit. If you can't brighten your dash by turning the headlight control ccw, then your variable resistor in the headlight control may be defective or the dimming circuit on the cluster circuit board is defective. Hope this helps.
Your always on lamp in the rearview mirror is only on when the headlight switch is in parking light or headlight position and its intensity is controlled by the dimming control on the headlight switch. The switchable maplight in the rearview mirror is a separate lamp and is not on the dimmer circuit. If you can't brighten your dash by turning the headlight control ccw, then your variable resistor in the headlight control may be defective or the dimming circuit on the cluster circuit board is defective. Hope this helps.
Instructor
Joined: Jul 2001
Posts: 114
Likes: 0
From: Whittier CA
Re: Electrical Help - Interior dims to black after dark (jaa1988)
Hey there, did you by chance install an aftermarket radio? If so, I had the same problem as you. Lights would work fine during the day, but at night, I would have no interior lighting. It turned out that the adaptor harness for the aftermarket radio was not completely compatible with the stock wiring. It would blow the fuse whenever the radio was turned on. Check the harness. You only need the power, ground, antenna and constant 12+ (and of course the speaker wires if you're not running an AMP). Remove all unecessary connections and everything will be fine. :)
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Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 7,999
Likes: 14
From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Re: Electrical Help - Interior dims to black after dark (jfb)
Check the inst fuse again and also make sure that the radio dimmer wire you taped is not touching ground.
Gordon Kilebrew diagnosed my blower problem - the blower is gone so I'll replace it when I get home.
Thanks all!!
Edit - replaced the blower moter Monday, all went well I now have air blowing out the vents. OBTW - I used a crimp connector for the wires I did not use just to avoid any grounding problems with the radio install. They work better than just wrapping with tape.
[Modified by jaa1988, 2:40 PM 5/28/2002]
