Summary: Radio doesn't dim despite 12 V on the red/black wire going into it. (A3)
THANKS in advance for any insights on this in my 2001 NSX-T. The only thread I could find on my search was @I_M_Legend thread somewhat similar issue which started out similarly, or perhaps the opposite?
and also:
Workup:
Does anyone have enough of an understanding of the factory radio to suggest things to check and repair?
THANKS in advance for any insights on this in my 2001 NSX-T. The only thread I could find on my search was @I_M_Legend thread somewhat similar issue which started out similarly, or perhaps the opposite?
Help Needed - Electrical Issue
My stock radio unit has been acting up lately. It thinks I've turned on the lights when I haven't. I'll be driving along and then notice that the display has dimmed and the buttons illuminated as if I turned on my headlights / switched on parking lights. The display on the climate control is...
www.nsxprime.com
Car thinks lights are on, but they are not. Loose switch?
My climate control and radio backlight will dim (as if the lights are turned on) randomly and then come back on bright as usual. Sometimes when I turn the car off I'll get the "lights are on" alarm even if the lights are switched off. Any idea what faulty switch or relay may be causing this?
www.nsxprime.com
Workup:
- (Probably unrelated) Months ago, I changed the brake/tail light bulbs for red LEDs, and the T10 running bulbs in the rear lights as well. I grounded the bulb-out indicator wire in C563 to stop the bulb-out indicator on the dash. This worked fine for months.
- (Possibly related to this? But I can't see how looking at the wiring diagram.) A few weeks ago, I disconnected the tail light circuit at f5 in C563 and powered the Right tail lights with ignition-on power from C535. I did the same with f5 in C557 for the Left tail lights. According to the wiring diagram as I read it, there was nothing else connected to f5 past that connector, and I wouldn't think disconnecting the previous supply to the running lights would have any affect. Perfect, the tail lights came on with the ignition, as desired, but...
- Problems - 2:
- The brake light-out indicator started coming on again. When I investigated, I discovered that the previously installed ground from the bulb-out bypass at C535 was loose, perhaps bumped when I was repinning C563. I replaced the shunt from the bulb-out bypass, which solved the bulb-out indicator problem.
- The radio would dim, sometimes flickering back and forth a couple of times on starting and then staying dim, even if the lights weren't on. Voltage was leaking into that red/black for the radio but nothing else? (The climate control dimming still worked.) If I turned my running lights on, the radio would dim as expected, but would not "un-dim" when I turned the lights off, like there was stray voltage keeping the "lights on" wire hot, or hot enough to trigger dimming.
- (I drove like this for a few hours until I could get to trying to fix it.)
- The radio has now stopped its always-dimming problem, but now will not dim at all when I turn the lights on.
- The climate control unit and clock illuminate fine and dim properly when I turn on the running lights.
- As a test, I undid the repinning of the tail lights at C563 and C557 back to the OEM wires. The tails now come on normally with the lights switch, but the radio still does not dim. The radio works fine and so do the running lights, just no radio display dimming. There must be voltage on the red/black since it makes the running lights come on, but the radio doesn't seem to get the message.
- As the last test, I checked for voltage on the red/black that feeds into the radio. Both with the radio connected, and with it unplugged, I measure 12.7 V at the red/black feeding into the radio with the lights on, about 0.5 V with lights off, so it should be getting the signal to dim and illuminate things. So my assumption is that the radio is the problem.
- Blown fuse? (Can't figure out which one.) Hoping @Old Guy or @drew have some insight. Fuses in the Radio? For the dimming?
- Crossed a wire and shorted something out in the radio somehow while swapping the wiring at the tail light and the dimming circuit is permanently damaged. This makes no sense as 12 V to this wire should not cause a problem, just put on the illumination. (I can't figure out what accidentally grounding the red/black with the running lights off would do as it's already pretty low resistance to ground through all those running lights. It would blow the fuses 38 & 39 if it was grounded with the running lights on.)
- Capacitor problem in the radio suddenly presenting in this way, coincidentally at the same time?? @Heineken ?
Does anyone have enough of an understanding of the factory radio to suggest things to check and repair?
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