Greetings friends, it been a while since I posted, but then again its been a while since I had problems with my 99 Accord Lx 4Cy. But I know I can count on the experts on this site.

A while ago I spilled water on my AC controls and it stopped working and I couldn't do anything but change the AC speed on with the *****. I bought a replacement AC panel off of Ebay and it was exactly the same except for the hazard switch. After replaceing the panel the AC controls worked great and everything seemed fixed except I had no turn signals whatsoever now. I checked fused and connections and eventually I came to switch the hazard switch from my old panel. This worked and I had turn signals again. I thought that was the end of it so I left it like that until later that evening when my wife told me that the dash lights didn't turn on. I checked it and I noticed that instrument lighs, dash lights and spedometer LCD lights did not turn on. Infact the LCD light and shift indicator turns off when I turn on the vehicle headlights. I checked fuses, connections and even swithed back everything the way it was before any of this (hazard and panel) but it remains the same regardless of what I do. Everything else works fine such as the dome lights, brake lights, mirror lights, wipers and I even changed most of the related fuses just to be sure. Now I am stumped and don't know where to proceed with the troubleshooting. Any suggestions would be appreciated, thanks.

 

I don't know much about this, but if the fuse didn't blow, then it could be the LEDs themselves.... Mine went out on my minivan, same issue... it was the LEDs...

 

Im going to take apart the dash this weekend and test the lights but I don't think all the lights would go out at the same time.

 

Have you tried tapping when your hand on the cluster? i used to do that and my leds would sometimes come on. It be intresting on your finding, and if it is the leds can we see pics i gotta do this as well thanks in advance.

 

First the obvious dumb question I'll ask, did you try turning the adjustment to made sure it is not set all the way dark?

You didn't mention which fuses you checked.. did you check fuse 10 in the passenger under-dash fuse/relay box? While fuse 9 in the driver's under-dash fuse/relay box is part of the dash illumination circuit, I'm thinking it is good since you have the A/T indicators while the light switch is in the off position.

If the above fuse 10 is good, which I'm thinking it is since the gear indicator light goes out when you turn on the running/head lights. It could be a bad dash lights brightness controller in the gauge assembly, bad wiring between the gauge assembly and the driver's under-dash fuse/relay box, unlikely the driver's multiplex control unit is not seated in the driver's under-dash fuse/relay box well or the driver's multiplex control unit is bad or something related to it.

let us know where you are after looking into these.

 

First, in addition to the fuses I mentioned before check fuse 13 in the passenger's side fuse/relay box, it is used by the driver's side multiplex unit.

To test the brightness controller, remove the gauge cluster and measure the resistance between B4 (RED/WHT) and B5 (WHT/RED) on the cluster. Should vary 0 to 20,000 ohms as the dial is rotated.

To test that the brightness control wires from the gauge cluster to the driver's are good reinstall the gauge cluster, remove the driver's side multiplex unit from the driver's side fuse/relay box. Measure the resistance between B3 and B4, should be 0-20,000 ohms as before.

To test if the problem is in the driver's side multiplex unit, remove the unit from the driver's side fuse/relay box. Turn the lights on and connect A20 (RED) in the fuse/relay socket box to ground, the dash lights should be a full brightness.

If you now suspect the driver's multiplex unit after looking into it I have directions for checking it for any DTCs that I can provide later.

 

Dimmer switch

 

Looks like you have a bad dimmer switch which is common for Honda's.