Rep Power: 0

I've been having a problem with my headlights. The low beams will come on sometimes and high will come on but it also turns on the lows at the same time. I've narrowed it down to the multiplex control box. Has anyone else had a similar problem? I looked at the wiring diagrams in the Haynes manual and it seems completely integrated in that control box. Does anyone have and insight or experience with this? Thanks.

 
Rep Power: 812

i havent seen this at all. there was a recall for a burnt wire that caused the lo beam to not turn on, but yours sounds like a problem with the whole system. is this control box something you can find at a junkyard and replace? its not worth messing with all those wires and circuits.

 
Rep Power: 249

^^^ i agree. See if you can find a box at a junkyard or on car-part.com and just replace the whole unit. It will save you a lot of hassle and headaches.

 
Rep Power: 0

Can you give me more informtion about the burnt wire recall. I'd like to exhaust other options before trying to replace the multiplex which the cost is around 300. I'm not really thrilled about it but if that is what I have to do then thats what I will do. Now the fuse/relay box is a component of the multiplex control box and the actual control box isn't servicable but I was curiouse if the headlights were controled on some other component. Thanks a ton.

 
Rep Power: 331

what year is your car? if it's a 7th gen, the headlights arent multiplexed. we have plain old traditional switch to relay wiring. replacing the "multiplex control box" whatever that is, isn't going to do anything for you. and even if it's something in the engine compartment fusebox, there is no reason why you wouldnt be able to bypass the internal headlight circuit and do the wiring outside of it to avoid spending 300 beans. if it's an 01-03, it's probably a blown headlight fuse. this causes the high and low to both come on, dim, because the bulb finds a different path to ground through the high beam circuit.

 
Rep Power: 0

Problem has been solved. It was a combination of things. First, a blown fuse which was overlooked while diagnosing was the cause of all the lamps to burn at the same time. Once the fused was replaced it was only the low beams that were not functioning. This malfunction was symptomatic of a recall which is available on the Honda web site and was so kindly mentioned in this thread. So a fuse and an hour at the dealership and I'm back in business. Thanks everyone for their contributions.

Please also note that Haynes manuals suck and the wire diagrams are not correct, at least for a 2001 coupe ex.