I have google searched the crap out of this issue and can't seem to figure it out. Hopefully someone has some ideas for me.

Currently both my Key Fob and my Dome Light are not working. However, the radio works just fine. I checked every single fuse and I'm getting continuity. Both under the hood and interior ones. The one I thought it was going to be was "backup" as from what I read it is in charge of both of these things. I checked it 3-4 times to make sure and I'm getting continuity. I even cleaned the leads a bit just in case. I also get continuity where the fuse goes in. I did however check the Dome Light fixture and I do not get continuity from one side to the other.

I really hope I'm missing something simple here guys. Any advice you can give is greatly appreciated. I try to do all the repairs I can for my Fit and it's saved me a butt load of money. And i'm a computer guy, not a car guy.

 

Forgive me if this sounds too obvious but you didn't say you had checked so:

1. Number one suspect for the key fob would be the battery. I've had to change mine twice. It levers open with a coin or thick screwdriver. The battery is a standard button type.

2. Number one suspect for the light would be the lamp. You said you get open circuit across the light fitting. With the lamp fitted that would indicate a blown lamp. With the lamp removed that would be a normal reading. You could check that there is voltage present but first I would put a multimeter across the lamp.

 

Forgive me for leaving out obvious things. First thing I did was replace that battery in the key fob lol.

First thing I did was change the bulb as it's gone out before because they are cheap bulbs from China. As for the dome light, there is no continuity where the bulb goes in from one lead to the other. The continuity I was talking about in my original post was just for the fuses. Sorry for not being clear!

 

There isn't supposed to be continuity there; there's supposed to be voltage there when the light is switched on.

 

Doesn't power need to be a circuit to work? i figured there would be power going from once side of the bulb to the other...

 

Of course, and that's what I said. There will be voltage there. That's what happens when the light is switched on.

If you don't have 12 volts across the bulb contacts with the light switched on, then you have a blown fuse, or a bad switch, or a cut wire somewhere.

 

I wish it was the fuse. When i saw that the dome light/key fob are both affected by the same fuse I was sure of it. But then i saw the radio was too. And that works fine. I checked every single fuse in that box to make sure and not a single one was blown.

So I fear I'm going to have to try to figure out the wiring. Do you know anywhere I could find a tutorial that would help me achieve that without buying that expensive book on it?

Once I get to where I need to be I can just test all the wires.

 

Are you sure your meter is good? Try measuring the voltage across a lit bulb such as one of the map lights, cargo area lamp, or license plate lamps.

It's basic low voltage automotive electrical troubleshooting. Google it. Here's one find: How to Diagnose Car Electrical Problems by Tracing Voltage Drops

 

Can I clarify one point? Are you saying the interior light doesn't work at all regardless of switch position or whether a door is open? Or are you saying it doesn't light when you press the button on the key fob? In other words is there one issue or two here?

If you want to do a voltage test at the light switch then the process is detailed here:

Ceiling Light Test/Replacement

And tests for the control circuit here:

Entry Light Control Circuit Input Test

If there isn't any voltage at all at the light switch with the doors then you will have to trace the problem back. Keep going until you get voltage and then you will know where continuity is lost.

If there is voltage at the switch then the earth side of the lamp is open circuit to earth. Either trace that back or find a new earth for it.

Regarding the key fob. Don't take offense because we have all done it and double check that you have that new battery fitted the right way round in the key fob. If the battery is fresh and fitted correctly then you you will need to look at the control circuit. here:

Power Door Lock Control Circuit Input Test

Of course the transmitter or receiver could also be faulty. Personally I would be happy enough to live without keyless entry given the difficulty and possible cost of repairing it if the transmitter or receiver unit is faulty. I'd get the interior light working though as that shouldn't be too difficult or expensive. You might find that a faulty connector or broken wire is causing both problems - it which case great.

 

Thank you sir! You have been most helpful. I'm going to perform these tests. And you were correct with this being two separate issues. The odd thing was that they went around the same time.

I have tested the keyfob at Advanced Auto Parts and it is giving out a signal according to their radio frequency test. It also lights up. I'm going to start with the dome light test you spoke of.

What I'm really hoping though is that since the keyfob and dome light are going to the same fuse then maybe wiring somewhere connects both the dome light/key fob at some point and just needs fixed up.

I'll provide updates with my progress and maybe help someone who might also run into this. Thanks again!

 

Well, you are welcome, good luck and happy hunting.

They might share an earth and that may be why they went together. When checking the connectors behind the instrument panel, I would probably start with the earths. You never know your luck.

Anyway, I'll be very interested to hear how you get on, not least because I may have to delve in behind that instrument panel one day and the manual is short on the tricky details.

 

Just had a look at the circuit diagram. The ceiling light is a bit unusual in that the switches all come after the lamp on the way back to earth. This is behind the instrument panel and yes, its earth at A9 is shared with the wireless receiver. Contact A9 would be my prime suspect but there are two other earths, A11 and A19. Make sure they all have continuity with each other and to earth.

One thing I don't understand though. If you switch the light on manually does it light? It should unless there is a second earth fault as the switch in the light has its own earth.

 

Haven't got a chance to test yet. But great info again sir! I will focus on A9,A11, and A19 to start.

To answer your question about the manual for the switch. No it does not. That was the first thing I tried when changing the bulb.

 

interior lighting often has switched ground not switched power, Making some of the tests work backwards.. Keep an eye out..

 

That strongly suggests that the problem is on the power side rather than the earth side or that the light switch, lamp holder or connector is faulty. It will be very interesting to see if you find power at the lamp holder. Definitely start with that. When you test it, test with both its own earth and with a known good earth. Run a test wire to the battery earth or other convenient bit of bare metal under the hood if necessary.

 

Sorry for the delay. Things have been crazy for me lately. But I have some results!

A9,A11,A19 all have continuity to earth and each other.

On the dome light:
Wire 1 to 2 have no continuity
Wire 1 has continuity to the earth.
Wire 2 has continuity to the earth, but oddly my multimeter read -3.45 instead of .01 like it normally does.

 

The readings at the light are hard to understand. You don't say what switch position and that is important too. Here is what you should be getting. Between terminal 1 and 2 with the switch in middle you should be getting continuity, with some resistance, through the lamp. If not, then the lampholder or switch or connections to either has a fault. Or you have a faulty lamp.

Since you have found good earths it looks more like a fault on the power side. Switch your multimeter to volts DC and check if you are getting 12V at terminal 1 with the switch in the middle position.

Edit to add - Have you got a tailgate light? If so, is it working? If it isn't then it looks more and more like a power supply problem rather than an earth problem.

Power for both lights and the power lock control system comes from fuse 8 under the hood. Check if that is blown. If it is check for a short circuit to earth on the cold side of the fuse. If it isn't blown, then check that the fuse is getting power.

 

I disconnected the wire from the switch so it wasn't in any position. I was testing the wires directly.

The first thing I checked before anything was a blown fuse. That fuse also goes to the radio which is working perfectly. I'll check the other things you mentioned about the fuse.

I believe my tail light is fine, but i'll double check.

I will also check the voltage to the lamp. Something tells me it's something related to that. As I mentioned with wire 2 going to the earth the continuity was strange.

Thanks again sir!

 

OK, I understand what you were testing now. However, there is something wrong with these results because if both wire 1 and 2 have continuity to earth then they must have continuity with each other too.

Wire 1 (green/red) should have continuity to earth if a door is open and then it should have continuity for a minute or two. If the doors are all closed and after a couple of minutes then there should be no continuity to earth. If the control circuit is not working (likely as the locks aren't) then there should be no continuity to earth.

Wire 2 (white/red) should not have any continuity to earth - If there is then fuse 8 under hood will blow for sure. I'm not sure what you are measuring here but there is no such thing as negative resistance so it can't be right. There should be 12V on this wire so set your multimeter to volts DC and put the positive probe on the wire and the negative on earth. If you get 0V then check continuity to earth. If you have continuity then you have found your fault.

Fuse 8 also supplies the tailgate light (not tail light) so if you have one (I don't) it would be interesting to know if that is working. The audio unit is also, as you say, on that fuse, as wired by Honda. Beware people rewiring if you bought the car second hand. Someone might have "fixed" the problem by giving the radio a new supply.

If fuse 8 is good and there is power there which sounds likely but there is no power at the ceiling light or wireless receiver unit then it sounds like there is a broken connection or broken wire. If the radio is still on that circuit then looking at the wiring harness diagrams it seems to me that the most likely place to find the fault would be behind or under the under dash fuse unit where the harness splits and goes off to the dashboard control unit, radio, ceiling lights and tailgate light. It will be a matter or tracing the harness back until power disappears and then replacing the stretch of wire or repairing a connection.

Edit to add: One more thought on the radio. It has two power supplies. One permanently live via fuse 8 and white/red wire and another switched acc via fuse 17 underdash and yellow/red wire. I assume the fuse 8 one is for the clock and antitheft (if fitted) while the other is to make tunes. So, the radio working may not say anything about the circuit we are worried about.

 

Making progress. I had my brother kind of help me through some things. Turns out the Dome was getting power. But I was using an LED bulb. Low and behold I put a regular bulb in and it turned right on. SMH.

So now I'm still going to work with the Keyless entry issue and try to trace the wiring to find the issue. Can you link me to the wiring diagram you were talking about? I currently have the dash taken apart where the speedometer is an such. I think i'm going to have to tear some more stuff apart to find the broken connection.

PS thanks again for ur help.